Term
|
Definition
| – Atrial depolarization - denotes the cardiac muscle cells in the atrium are contracting. |
|
|
Term
|
Definition
| – Ventricular depolarization – denotes the cardiac muscle cells in the ventricle are contracting. |
|
|
Term
|
Definition
| – Ventricular repolarization |
|
|
Term
|
Definition
– P wave and QRS wave – contraction of the chambers
- as the atrium/ventricles contract, blood would move out of the chambers |
|
|
Term
|
Definition
– T wave – Ventricular relaxation
– relaxing, chambers filling up with blood |
|
|
Term
| If you count 75 beats/minute, how long would your cardiac cycle be in beats per second? |
|
Definition
| 75 beats/min = 60 (sec/min)/75 (beats/min) = .8 seconds/beat or cardiac cycle |
|
|
Term
| Blood flows from the large veins into the atria (Venous Return) |
|
Definition
| Flow because of blood pressure gradient (high in veins, low in atria) |
|
|
Term
| Blood flows from the atrium to the ventricles (P wave) |
|
Definition
The AV valve opens, semilunar valves are closed.
70% of blood flows passively (high to low) into the ventricles from the atria. Other 30% enters into the ventricles when the atria contract (30% atrial systole). |
|
|
Term
| blood flow from ventricle into the large arteries (QRS wave) |
|
Definition
Ventricular systole. The AV valves close and semilunar valves open.
The turbulence of the blood at the AV valve this is the first heart sound “LUB”. |
|
|
Term
| Ventricles go into diastole (just after T wave). |
|
Definition
| As diastole begins the semilunar valves close. Blood rushing against the closed valve produces the second heart sound “DUP”. |
|
|
Term
| heart sounds, First “Lub” |
|
Definition
• Associated with QRS wave
• Get ventricle systole
• AV valves close
• Turbulence produces vibrations. First heart sound heard close to the apex of the heart |
|
|
Term
| heart sounds, Second “Dup” |
|
Definition
• Associated with T wave
• Ventricle - diastole and closing of semilunar valve
• Turbulence against the semilunar valve.
• Hear this to the left of the sternum, just below the clavicle |
|
|
Term
|
Definition
| Stream line flow of blood in the vessels. No sound produced. |
|
|
Term
|
Definition
| : Causes vibration – caused by turbulence. |
|
|
Term
|
Definition
| Devise used to measure blood pressure is |
|
|
Term
|
Definition
| Pulse Pressure = systolic pressure – diastolic pressure (120 – 90 = 30 mm Hg) |
|
|
Term
|
Definition
Mean Arterial Pressure – 1/3 pulse rate + diastolic (10 + 90 = 100 mmHg)
Indicates the average pressure in the arteries during one cardiac cycle |
|
|
Term
|
Definition
• Non contractile cardiac muscle cells
• Make up 1% of heart cells
• These cells can branch out to other cells. Between all cardiac muscles cells we have gap junctions |
|
|
Term
|
Definition
• Unstable potential – spontaneous drift up (on the curve)
• Voltage of these cells sits at -60mV
• Gradual drift up to -40mV (threshold)
1. Gradual decrease in K+ permeability (inside becomes more positive)
2. Increase in Na+ permeability
3. As soon as threshold reached an AP of the SA and AV nodes would fire. |
|
|
Term
| Depolarization phase of conduction system |
|
Definition
• Caused by an increase in Ca++ permeability (voltage gated ion channels open). Ca++ from extra cellular fluid.
• -40mV to just about 0 mV |
|
|
Term
| Repolarization Phase of conduction system |
|
Definition
• During this phase Ca++ voltage gates close. K+ voltage gates open
• 0 mV -60 mV
• No hyperpolarization because all K+ voltage gates close. |
|
|
Term
| In resting the heart repeats _____ times/minute |
|
Definition
|
|
Term
|
Definition
| – sets the heart rate – referred to as the “pace maker” |
|
|
Term
|
Definition
• the AV node can fire action potential at 60 beats/minute
• Purkinje – can also fire but only at 30 AP/minute. |
|
|
Term
| Contractile Myocardium (page 694) |
|
Definition
• Ventricular - having RMP of -90mV
• Action potential in Purkinje fibre stimulate the contractile myocardial cells (get depolarization) |
|
|
Term
| 4 stages of AP in ventricular myocardium |
|
Definition
a) depolarization
b) repolarization begins
c) plateau stage
d) repolarization continues |
|
|
Term
| depolarization ( AP of ventricular myocardium) |
|
Definition
• -90 mV 25 mV
• Explosive influx of Na+
• No graded potential – goes strait to action potential |
|
|
Term
| repolarization ( AP of ventricular myocardium) |
|
Definition
• Na+ gates begin to close
• K+ gates open (moves out)
• Membrane potential drops slightly |
|
|
Term
| plateau stage ( AP of ventricular myocardium) |
|
Definition
• Keeps membrane depolarized for about 250 ms. Prolongs the action potential
• During this phase the K+ voltage gates close and Ca++ voltage gates open (get Ca++ in) |
|
|
Term
| repolarization continues ( AP of ventricular myocardium) |
|
Definition
• Ca++ gates close
• K+ voltage gates re-open
• ***Absolute refractory period lasts 250 ms (prevents summation of contractions) |
|
|
Term
| Excitation-Contraction Coupling in the ventricular myocardium |
|
Definition
1) AP from Purkinje fibres stimulus for Ventricular Contraction Cells moves quickly through gap junctions (have channels – AP passes through). All ventricular cells contract at the same time.
2) Ca++ released from Sarcoplasmic Reticulum (voltage gates opening for diffusion)
3) Ca++ binds to troponin on thin myofilaments. Removes tropomyosin to expose the actin binding sites get sliding filament mechanism |
|
|
Term
| Just as depolarization begins, contraction begins. AP lasts __1__ ms. Twitch lasts __2__ ms. Because AP lasts as long as the Twitch, this prevents __3__. Heart functions as __4__ . |
|
Definition
1) 250 ms
2) 300 ms
3)wave summation
4) pump |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Less than 50 beats/ min |
|
|
Term
|
Definition
| No conduction through AV node (SA still firing). Ventricles beat at 30 beats/min, atria at 75 beats/min. Heart can not pump blood to the organs of the body. Pacemaker would need to be put into the body. |
|
|
Term
|
Definition
| – volume of blood pumped by each ventricle per minute. Measured in litres/min. |
|
|
Term
|
Definition
| CO = Heart Rate (HR) X Stroke Volume (SV) |
|
|
Term
|
Definition
| SV = volume of blood ejected from each ventricle per beat |
|
|
Term
| Sympathetic Nervous system, heart rate regulation |
|
Definition
• Impulses carried by the thoracic nerves
• Neurotransmitter Norepinephrine
• SA and AV nodes – NE increases Ca++ permeability and K+ permeability decreases (less out).
• Increase in rate of depolarization increase in heart rate
• Also innervates the ventricular myocardium (increases the force of contraction. NT binds faster) |
|
|
Term
| Parasympathetic Nervous System, heart rate regulation |
|
Definition
• Impulses carried by the Vagus nerve
• Neurotransmitter Ach
• SA and AV nodes – NT decreases Ca++ permeability, increases K+ at the SA and AV nodes, and the Ca++ and K+ levels change, there is less depolarizing, not hyperpolarizing
• Innervates the atrial myocardium (makes it more difficult to produce an AP) |
|
|
Term
| Hormones, heart rate regulation |
|
Definition
• 80% of the hormones produced from the Adrenal Medulla is Epinephrine.
• Epinephrine is significant to Heart rate
• Increased Ca++ permeability, increase frequency of AP heart rate increases
• Thyroid and Norepinephrine also function to increase heart rate. |
|
|
Term
| Ions, heart rate regulation |
|
Definition
• Low K+ ion concentration or high K+ concentration, both would cause a decrease in heart rate
• Low K+ hyperpolarize, high K+ ???
• Ca++ would increase heart rate
• Increase inCO2, and a decrease O2, heart goes up. |
|
|
Term
| End Diastolic Volume (EDV) |
|
Definition
| the volume of blood in each ventricle at the end of ventricular diastole. 120 mls (from atria to ventricles – passive flow) |
|
|
Term
| End Systolic Volume (ESV) |
|
Definition
| the volume of blood in each ventricle at the end of systole. 50 mls of the 120 mils remains in the ventricles after systole. |
|
|
Term
|
Definition
|
|
Term
|
Definition
| – a mechanism that operates entirely with in the organ. This intrinsic control is not affected by the nervous or endocrine systems. This control uses end diastolic volume (EDV) to regulate Stroke Volume. Intrinsic control is defined by “Starlings Law” when venous return to the heart changes, the heart automatically adjusts the output to match the venous return. |
|
|
Term
| Effect of EDV on SV (Starling’s Effect) |
|
Definition
• When venous return increase we get an increase in the EDV (causes the ventricle walls to stretch
• At rest the sarcomeres are shorter than optimal length. As the ventricle stretches the sarcomeres become optimal length. The result is more actin to bind to myosin. Get greater tension. This causes the increase in force of contraction
• When the force increase, the stroke volume increases. |
|
|
Term
| Factors that effect the EDV |
|
Definition
Intrinsic Control
extrinsic control |
|
|
Term
Increased Venous Return =
Decreased Venous Return = |
|
Definition
Increased Venous Return = increased EDV
Decreased Venous Return = decreased EDV |
|
|
Term
|
Definition
|
|
Term
| Filling time of ventricles |
|
Definition
• Depends on the heart rate
• Low heart rate (60 bpm) – ventricle remain in diastole for 0.6 seconds (more time for the ventricles to fill up more)
• High heart rate (150 bpm) – ventricles remain in diastole over a shorter period of time (0.1 sec in diastole – less time to fill up ventricles) |
|
|
Term
| Arterial Blood Pressure – Hypertension (Chronic High BP) |
|
Definition
• Because blood pressure is high the ventricles have to work harder to push blood into the arteries (difficult to get blood out)
• After ventricle systole, the ESV increase – eventual goes above normal.
• Because the heart has to work so hard, it begins to enlarge. This can lead to heart failure. |
|
|
Term
|
Definition
|
|
Term
|
Definition
– Innervates the SA and AV node, ventricular and atrial myocardium
• Innervates ventricular myocardium
• Causes increase in force of contraction. Stroke volume would increase (Ca++ entering into ventricular cells) |
|
|
Term
| Extrinsic control - hormones (Epinephrine) |
|
Definition
– most significant
• Cause increase in force of contraction
• Increases Stroke volume
• Increase heart rate |
|
|
Term
| Extrinsic control - hormones (Thyroid Hormones ) |
|
Definition
| – these hormones increase when exercising (increases the metabolism higher then normal). Force of contraction increases. |
|
|
Term
|
Definition
| – The volume of blood flowing in a blood vessel/organ per minute |
|
|
Term
|
Definition
| – force exerted by blood on the walls of the blood vessel (hydro static pressure in the arteries) |
|
|
Term
|
Definition
| – as the blood flows through the blood vessels, the blood at the side of the vessel produces friction. This resistance hinders the smooth flow of blood. |
|
|
Term
| Total peripheral resistance (tPR) |
|
Definition
| • Total resistance in all blood vessels of the system circulation. |
|
|
Term
|
Definition
1) Length of the blood vessel
• The longer the greater the resistance
2) Viscosity of blood
• The thickness of blood
The above two would not normally change in a healthy person.
3) Radius of the arterioles |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| if F = Blood Flow, R = resistance in arterioles and ∆P = blood pressure gradient between 2 points: then F= |
|
Definition
F = ∆P/R
ex: / Aorta – 90 mm Hg
∆P
\ Right Atrium – 0 mm Hg |
|
|
Term
Blood flow directly proportional to blood pressure gradient:
• if flow increases then ...
• if ∆P decreases then ... |
|
Definition
• if flow increases, then ∆P increases
• if ∆P decreases, then flow decreases |
|
|
Term
Blood flow is indirectly proportional to resistance:
• if resistance increases then ...
• if resistance decreases then... |
|
Definition
• if resistance increases then blood flow decreases
• if resistance decreases then blood flow increases |
|
|
Term
| A decrease in the number of impulses from the SNS results in... |
|
Definition
|
|
Term
| An increase in the number of impulses from the SNS results in... |
|
Definition
| – arterioles constrict (Blood flow decreases, but more blood in arteries. Blood pressure increases in the arteries) |
|
|
Term
| Intrinsic control (occurs inside of organ – local control): in response to the chemical environment within an organ |
|
Definition
Increase in metabolic activity need to breakdown food for energy
• have increase in cellular respiration (produces ATP)
• increase in production of CO2
• Also drop in oxygen (used for cellular respiration)
• Build up of lactic acid (means an increase in hydrogen (H+) ion concentration)
• The Arteries respond to a build up of these end products (which are the stimulus) by dilating and blood flow increase. |
|
|
Term
| Intrinsic control: Arterioles respond to stretch |
|
Definition
In brain – arterioles sense change in Blood Pressure.
• If Blood pressure increases the blood vessels would sense an increase in blood pressure and then they would constrict and blood flow to brain would decrease. Opposite is true.
• This is called myogenic response. |
|
|
Term
| Extrinsic control - hormones (Angiotensin II ) |
|
Definition
– very powerful vasoconstrictor
• Also causes the veins to constrict (venous constriction) |
|
|
Term
| Extrinsic control - hormones (Histamine) |
|
Definition
|
|
Term
| Extrinsic control - hormones (ADH) |
|
Definition
| – Causes vasoconstriction |
|
|
Term
|
Definition
• Are nerve endings in the smooth muscle of the aorta regulates blood pressure in the body
• Also found in carotid artery regulates blood pressure in the brain |
|
|
Term
|
Definition
i) Drop in MAP (short regulation – seconds to minutes)
ex: getting up quickly – blood pressure drops
• Baroreceptor puts BP back to homeostasis
• Drop in BP does not stimulate the baroreceptor reduction in AP propagation to the CV centre
• Two things can happen
a) increase of impulses from SNS and get decrease in PSNS activity
• SNS - ↑HR, ↑ FC, ↑tPR (due to vasoconstriction)
*example of negative feed back ↓BP ~~~ ↑BP
ii) Increase in blood pressure
• Baroreceptors are stretched increase in AP to CV centre
• Increase in PSNS activity
PSNS ↓HR ↓tPR |
|
|
Term
|
Definition
– chronic higher blood pressure
• Occurs over years
• Baroreceptors only pick up the stretch at higher then normal levels. |
|
|
Term
|
Definition
• Also function to regulate BP
• Found in aorta and carotid arteries
• They are sensitive to chemicals specifically CO2 and O2
• Especially to ↑CO2 and ↓O2
• Chemoreceptors also referred to as aortic or carotid bodies
• This reflex is important when BP is low
• Acts as a back up to the baroreceptors. |
|
|
Term
| Hormones - regulation of tPR and heart rate |
|
Definition
When blood pressure is low – hormones released
a) Glucocorticoids – ex cortisol from adrenal cortex
b) Epinephrine, Norepinephrine – from adrenal medulla
Above hormones cause vasoconstriction |
|
|
Term
| Renin – Angiotensin – Aldosterone Pathway |
|
Definition
• Activated when there is a severe drop in blood pressure (ex: loosing blood/hemorrhaging)
• Angiotensin (plasma protein always present in blood- produced in liver). Converted by Renin (enzyme produced by the kidneys) into Angiotensin II
• Angiotensin Converted by Renin into Angiotensin II |
|
|
Term
| Effects of Angiotensin II |
|
Definition
• Very powerful vasoconstrictor
• Causes BP to increase.
i) Vasoconstriction of arterioles and the arteries
ii) Venoconstriction - ↑VR
iii) Increase secretion of Aldosterone – secreted from the adrenal cortex – increases blood volume (using sodium) ↑SV
iv) ↑Secretion of ADH (Antidiuretic Hormone). Released from the posterior pituitary gland. ADH also a vasoconstrictor, increase blood volume by reducing the excretion of urine. Also increase thirst. |
|
|
Term
| When Blood Pressure is High... |
|
Definition
• Atrial Natriuretic Peptide (ANP – hormone) released from the cells of the atrium. Increases urine output blood volume decreases, decrease in Stroke Volume
• Also inhibits the secretion of ADH |
|
|
Term
|
Definition
| • Drop in blood flow to cells and organs (CO decreases) |
|
|
Term
| Hypovolemic shock (below volume) |
|
Definition
• Decrease in blood volume, caused by severe hemorrhage, diarrhea, excessive vomiting, burns
• Causes a ↓BP
• HR ↑, massive tPR (from angiotensin)
• Only way to treat is to replace the los blood medically – either with more blood or saline solution |
|
|
Term
|
Definition
• Extreme vasodilation of all blood vessels ↓BP
Ex: anaphylactic shock – peanut allergy
• BP ↓ drastically
• Release of histamine (vasodilation)
• Treated by injecting adrenalin (epi-pen – constrict the blood vessel) |
|
|
Term
|
Definition
– infection bacteria release toxins
• Major vasodilation
• Require antibiotics |
|
|
Term
|
Definition
• May occur in some one who has had a number of heart attacks
• Heart can not maintain cardiac output
• Results in lower BP and ↓CO
• CO – to get blood to cells so they get oxygen, otherwise cells begin to die (medical treatment required) |
|
|
Term
| Shock can result in the following: |
|
Definition
• SNS activated
• Adrenal medulla (secreting NE and E)
• Angiotensin II released) |
|
|
Term
|
Definition
• The exchange between the blood in the capillaries and the interstitial fluid (IF)
• Blood flow in the capillaries is very slow
• Make it easy for exchange of gases and nutrients
• Most cells are located within .1mm of the fluid capillaries |
|
|
Term
| Substances Enter and Leave Blood Capillaries by: |
|
Definition
1) Simple diffusion
2) Transcytosis – (includes Exocytosis & Endocytosis)
3) Filtration and Reabsorption |
|
|
Term
|
Definition
| • Allows CO2 and O2, steroid hormones (fat soluble), fatty acids, move across the cell membrane |
|
|
Term
| Transcytosis – (includes Exocytosis & Endocytosis) |
|
Definition
• Large lipid solids moving across (into and out of the IF)
• Requires ATP |
|
|
Term
| Filtration and Reabsorption |
|
Definition
• “Bulk Flow” – movement of water and anything dissolved in it (solutes)
• Passive process
• Because of pressure gradient
• A) Filtration – movement of substances from the blood capillaries into the interstitial fluid
• B) Reabsorption – movement from the IF into the blood capillaries. |
|
|
Term
|
Definition
BHP – Blood Hydrostatic Pressure in the blood capillaries
BOP – Blood Osmotic Pressure in the blood capillaries
IFHP – Interstitial Fluid Hydrostatic pressure outside of capillaries
IFOP – Interstitial Fluid Osmotic Pressure outside of capillaries |
|
|
Term
| At the arterial end of capillary there are 3 forces acting on the capillary: |
|
Definition
a) BOP – draws in (35 mmHg)
b) BHP – pushes out (28 mmHg)
c) IFHP – pushes out (3 mmHg) |
|
|
Term
|
Definition
– swelling of tissues between the cells
1) Hypertension (chronic) causes ↑BHP – increase in filtration (ex: ankles become swollen)
2) Blood OP↓ (caused by malnutrition, liver disease – less proteins in blood)
Filtration will occur, but ↓reabsorption. Fluid remains around the cells
3) ↑IFOP (more protein in IF – caused by allergic reactions)
↑filtration, ↓reabsorption
4) 10% in lymph – surgery, blocked by cancer, parasites
• Get swelling |
|
|
Term
|
Definition
• 90% water
• Proteins (produce BOP) – 8% (most supplied by the liver)
• Solute – glucose, nutrients, vitamins, O2, CO2 |
|
|
Term
| main proteins in the blood plasma |
|
Definition
- made by the liver
a) Albumin – important for Osmotic Pressure
b) Fibrinogen – (extremely important) for blood clot formation
c) Globulin – part of immune system (antibodies) |
|
|
Term
|
Definition
• Matured cells lack a nucleus (enucleated)
• Last 120 days (destroyed by liver)
• Contains hemoglobin (Hb) which is a red protein pigment that consists of two components: heme and gamma globin |
|
|
Term
|
Definition
- red pigment, contains iron.
functions to bind and transport oxygen.
- some is recycled after the cell is destroyed.
- balance of heme becomes bilirubin and is excrete in bile. |
|
|
Term
|
Definition
- protein – transports CO2
- 20% of CO2 is transported by globin. This is called carbaminohemglobin.
- when the RBC is destroyed the globin is broken down into amino acids and recycled. |
|
|
Term
|
Definition
Also called Leukocytes, 2 types:
1) Granulocytes
2) Agranulocytes |
|
|
Term
|
Definition
a) Neutrophils
b) Eosinophils
c) Basophils |
|
|
Term
|
Definition
a) Lymphocytes
b) Monocytes |
|
|
Term
|
Definition
• Phagocytic cells that engulf microbes, bacteria, etc and destroy it.
• First cells to enter an inflamed area.
• Ex: cut – attack bacterial and fungi in the area. |
|
|
Term
|
Definition
• Part of system which attacks microbes especially parasitic worms
• Decrease inflammation |
|
|
Term
|
Definition
• Release 2 chemicals: Histamine (induces vasodilation)
Heparin (decreases clot formation) |
|
|
Term
|
Definition
• T lymphocytes – destroy microbes directly
• B lymphocytes – enlarge to produce a plasma cell produce antibodies |
|
|
Term
|
Definition
• Become cells called macrophages
• Macrophages – can wander to damaged tissue and would function to get rid of dirt or bacterial through phagocytosis |
|
|
Term
|
Definition
– are fragments of cells that consist of little bits of cytoplasm surrounded by a membrane.
• Produced from a large cell called a megakaryocyte that breaks up
• Essential for the clotting of blood. Forms plugs (platelets stick together).
• Produce factors (platelet factors – also necessary for blood clotting) |
|
|
Term
|
Definition
| is the process used to stop bleeding in the body. |
|
|
Term
| 3 processes involved at injured area during homeostasis |
|
Definition
1) Vascular Spasm
2) Platelet Plug Formation
3) Coagulation |
|
|
Term
|
Definition
– Blood vessels constrict causing a decrease in blood flow
• Caused by chemicals released at the site of the injury |
|
|
Term
|
Definition
• Platelets enlarge and become sticky
• Platelets stick together to form a plug – stops blood loss.
• Plug releases more chemicals and more platelets stick, releasing more chemicals….example of positive feed back. |
|
|
Term
|
Definition
– clot formation
• Liquid blood becomes gel. |
|
|
Term
|
Definition
• Cascade of events, also positive feed back.
1) Production of prothrombin activator
2) Prothrombin converted to Thrombin
3) Fibrinogen converted to Fibrin |
|
|
Term
| 1) Production of prothrombin activator |
|
Definition
• Injury triggers 2 pathways
i) Extrinsic Pathway: at sight of injury certain factors (factors are proteins) are released from the damaged cells.
ii) Intrinsic Pathway: factors needed are in the blood.
• Both above pathways release factors
• Both require Ca++
• Approx 2 doz. Factors are required for clot formation |
|
|
Term
| 2) Prothrombin converted to Thrombin |
|
Definition
Prothrombin (plasma protien)
--> conversion (requires prothrombin, activator, Ca++, factors)
--> Thrombin (enzyme) |
|
|
Term
| Fibrinogen converted to Fibrin |
|
Definition
• For this conversion to happen we need to have thrombin, Ca++ and factors present
• Fibrin is an insoluble fiber – forms a mesh over the RBC trapping the RBC, and the platelet plug. |
|
|
Term
| Clot Retraction and Blood Vessel Repair |
|
Definition
• Platelets contain actin and myosin. They can contract so the edges of the blood vessel draw closer together
• Blood vessel repaired by connective tissue (epithelial cells) |
|
|
Term
| Fibrinolysis / Clot Digestion |
|
Definition
• Fibrin is broken up by an enzyme called plasmin (digests the clot)
• Plasmin produced by a plasma protein called plasminogen
• Takes 2 – 3 days
• Last bit of clot removed by phagocytes
• Plasmin can be injected into a person if they have a blood clot in their system |
|
|
Term
|
Definition
– Genetic condition
• Blood clotting is abnormal or absent
• Most people who have hemophilia have Type A hemophilia result of the absence of one particular factor…Factor VIII |
|
|
Term
|
Definition
• General response against disease
i) Surface barriers
ii) Internal Defences
iii) Antimicrobial proteins
iv) Inflammation response |
|
|
Term
|
Definition
|
|
Term
|
Definition
• phagocytes
• macrophages
• natural killer cells (lymphocytes – always on alert, can destroy cancer cells as well)
• gastric juice (food contains microbes, HCl in stomach -2pH- also kills microbes in food)
• in tears and saliva (have lysosomes)
• Moderate fever also functions to destroy microbes |
|
|
Term
| Antimicrobial proteins – ex: interferon |
|
Definition
| • Produced in body to defend against disease |
|
|
Term
|
Definition
In a cut the area becomes red, hot, and can swell.
• Cause by vasodilation from histamine
• Mast cells produce the histamine
• Neutrophils enter the injured area after about an hour. Remove dead cells dirt...etc. Prevents other microbes from getting into other areas of the body
• Get macrophages wandering through the body looking for bacteria |
|
|
Term
|
Definition
– Immunity
• Recognize specific foreign substances, bacteria (antigens) and the immune system will produce antibodies to destroy the antigens
• Antigens – is the foreign substance (virus, bacterial, pollen, transplanted organ)
• Antibodies – protein gamma globulin. Produced from plasma cells. Antibodies combine with antigens. |
|
|
Term
|
Definition
1) Cell Mediated Immunity
2) Antibody Mediated Immunity/ Humoral Response |
|
|
Term
|
Definition
| • T lymphocytes – destroy antigens by direct attack (viruses that hide, and antibodies can not get to them) |
|
|
Term
| Antibody Mediated Immunity / Humoral Immunity |
|
Definition
| • B lymphocytes – activated by an antigen. B lymphocyte becomes a plasma cell, produces antibodies specific to that antigen. |
|
|
Term
| Types of Humoral Immunity (humoral = antibodies) |
|
Definition
1) Active Humoral Immunity
2) Passive Humoral Immunity |
|
|
Term
|
Definition
a) Natural Humoral Immunity – Ex: when you get the flu, the body would attach that specific virus. T lymphocytes would destroy the virus; B lymphocytes produce antibodies against that virus
b) Artificial Humoral Immunity – Ex: when you get a flu shot
• Both cases your immune system will produce antibodies against this virus. Some will provide immunity for years. |
|
|
Term
|
Definition
• Can come from another person/animal
• Borrowed antibodies usually only good for 2 – 3 weeks
a) Natural Passive Immunity – Ex: from mother crosses over the placenta and gets into the fetal circulation.
b) Artificial Passive Immunity – Ex: Rabies Virus can be injected into a horse. Horse produces antibodies against virus. The antibodies are collected from the horse and inject into a person. |
|
|
Term
|
Definition
| Kills T Lymphocytes and prevents B lymphocytes from producing antibodies. Immune system destroyed. |
|
|
Term
| Respiration is the overall exchange of gases. 3 processes are involved: |
|
Definition
1) Pulmonary Ventilation (Breathing)
2) External Respiration
3) Internal Respiration |
|
|
Term
| 1) Pulmonary Ventilation (Breathing) |
|
Definition
i. Inspiration – inhale
ii. Expiration – exhale
Exchange of air from the atmosphere and into the lungs |
|
|
Term
|
Definition
– Pulmonary gas exchange
• Exchange of O2 andCO2 between lungs and blood |
|
|
Term
|
Definition
|
|
Term
|
Definition
• Pressure required for respiration
• Inside of lungs (air), in the alveoli. |
|
|
Term
|
Definition
• Fluid pressure in the pleural cavity
• Serous fluid – between the parietal and visceral pleura
• This pressure is less than intrapulmonary pressure and less than atmospheric pressure
• Described as a negative pressure (creates a vacuum) which functions to keep the lungs inflated |
|
|
Term
|
Definition
| • Pressure of the air that surrounds us, equal to 760 mmHg |
|
|
Term
|
Definition
– as the volume of air increase its pressure decreases
• Volume is indirectly proportional to pressure - ↑Volume = ↓pressure |
|
|
Term
|
Definition
| – is the pressure exerted by a single gas in a mixture of gases. |
|
|
Term
Pulmonary Ventilation
a) Quiet Inspiration |
|
Definition
• Contraction of the diaphragm and external intercostal muscles which causes an increase of size in the thoracic cavity
• Area increases because contraction causes the diaphragm to flatten, the intercostals to raise the ribs up and the sternum to push forward
• Intrapleural pressure will drop to 754 mmHg
• Volume of the lungs will increase (negative pressure sucks the lung out)
• Intrapulmonary pressure drops to 758 mmHg
• Air rushed in because atmospheric pressure is higher then in the lungs (atm 760 mmHg)
• This considered an active process because the muscles of the diaphragm and intercostals contract. |
|
|
Term
Pulmonary Ventilation
Forced (deep) Inspiration |
|
Definition
– during exercise, asthmatic attack…
• Same as above happens
• Also get the sternocleidomastoid muscles, scalene muscles, and pectoralis minor contracting increasing the thoracic cavity size
• Pressure gradient is wider |
|
|
Term
Pulmonary Ventilation
b) Quiet Expiration |
|
Definition
b) Quiet Expiration (Lungs Atmosphere)
• Diaphragm and external intercostal muscles relax decreasing the volume of the thoracic cavity
• Intrapleural pressure increases pushing against the lungs.
• Lungs “recoil” causing the volume in the lungs to decrease
• Intrapulmonary pressure increases to 762 mmHg
• Air moves out of the lungs because the pressure inside lungs is higher then outside.
• Passive process |
|
|
Term
Pulmonary Ventilation
Forces Expiration |
|
Definition
• Abdominal muscles contract (active process because the Abdominal muscles are contracting)
• Contraction pushed up against the diaphragm (more dome shaped) and pulls the ribs down decreasing the thoracic cavity space.
• Air rushes out. |
|
|
Term
|
Definition
• Caused by a stab wound or pneumonia
• Intrapleural pressure becomes the same as atmospheric pressure because air is moving into the intrapleural cavity
• Lungs will collapse |
|
|
Term
|
Definition
• Mixture of lipids and proteins
• Reduces the surface tension of the water lining the alveoli – prevents the alveoli from collapsing
• Surfactant decreases the work of breathing – increases “compliance”
• Compliance is the ability to expand |
|
|
Term
| Respiratory Distress Syndrome |
|
Definition
• Present in newborns that are premature (before 7 months gestation)
• Lungs do not produce sufficient amounts of surfactant
• Becomes difficult to keep the lungs inflated and requires more energy to re-inflate the lungs. This results in the respiratory muscles becoming overworked
• Babies will be put on an artificial respirator or given surfactant. |
|
|
Term
|
Definition
| this is a result of the attraction of water molecules to each other. The surfactant reduces the surface tension by making it easier for the water molecules to separate. |
|
|
Term
|
Definition
| • Volume of air that is inspired and expired at rest (500 ml ~) |
|
|
Term
| Inspiration Reserve Volume (IRV) |
|
Definition
| • Excess air that can be taken in with a deep breath. Occurs after the relaxed inhalation (3100 ml~) |
|
|
Term
| Expiratory Reserve Volume (ERV) |
|
Definition
| • Maximum amount of air that can be pushed out after normal expiration (1200ml ~) |
|
|
Term
|
Definition
• Volume of air that remains in the lungs after maximum respiration (1200ml ~)
• This is important for 2 reasons a) it allows lungs to inflate easier,
b) always air in the lungs to allow gas exchange. |
|
|
Term
|
Definition
| Inspiratory Capacity = TV + IRV |
|
|
Term
|
Definition
| Vital Capacity = TV + IRV + ERV |
|
|
Term
|
Definition
| Lung Capacity= TV + IRV + ERV + RV (6L of air) |
|
|
Term
| Forced Expiratory Volume (FEV1.0) After 1 second |
|
Definition
| • Volume of air that is expired during the first second of expiration |
|
|
Term
|
Definition
| Increases the resistance to air flow. Ex: Asthma, Emphysema, cystic fibrosis. FEV decreases |
|
|
Term
|
Definition
| condition that prevents the lungs from inflating normally. Ex: Scoliosis (thoracic cavity area is reduced), Pneumothorax. FEV decreases. |
|
|
Term
|
Definition
• Pulmonary gas exchange between alveoli of the lungs and the blood
• Blood is deoxygenated travels to lungs CO2 removed and O2 picked up.
• Both happen because of partial pressure differences
• Junction between the alveolus and the capillary is very thin (2 cells thick)
• In the lungs are an extreme large number of alveoli/lungs are highly vascular
• Blood that is flowing in the capillaries flow very slowly |
|
|
Term
|
Definition
| • Exchange between the blood and the cells of the body |
|
|
Term
| Oxygen is transported in the blood 2 ways: |
|
Definition
1) Dissolved in Plasma – 3% of all oxygen is transported this way
2) Combines with Hb – 97% of oxygen |
|
|
Term
| Oxygen – Hb dissociation curve (See page 850, fig. 22.20) |
|
Definition
• Shows the relationship between:
PO2 and % of HbO2
• The higher PO2 the greater the amount of HbO2
• Graph broken down into two parts:
i) Plateau – PO2 goes from ~60 to 100 mmHg
ii) Steep Part of Graph - PO2 goes from 0 to 60 mmHg |
|
|
Term
|
Definition
• Represents what is happening at the lungs
• PO2 is 100 mmHg
• Hb is 97% saturated with O2
• Even with a drop from 100 – 60 mmHg, the blood will still have at least 90% O2 saturation. |
|
|
Term
|
Definition
Tissue Metabolically Active
• Represents the blood in the tissues
• PO2 is low – 40 mmHg
• Blood has given up the oxygen – 75% Saturation of O2 (deoxygenated blood) |
|
|
Term
| Shift to right in the dissociation curve |
|
Definition
• The following causes are involved in metabolic activity (exercise)
i) Rise in body temperature
ii) Drop in pH (because of production of lactic acid
iii) Increase in Carbon Dioxide
• Less oxyhemoglobin because blood is unloading oxygen which is required for metabolic activity
• Bohr Effect – effect of pH on the blood
HbO2(unloaded) results in ↑H+ or (↓pH)
• Shift to right allows less oxygen to be bound to the Hb |
|
|
Term
| Shift to left in the dissociation curve |
|
Definition
• Indicates what is happening at the lungs
i) Decrease in temperature
ii) Increase in pH
iii) increase in PO2 (lots of oxygen at lungs)
• All the above allow oxygen to load on to the Hb |
|
|
Term
| Carbon Monoxide Poisoning: |
|
Definition
• CO competes with oxygen for the binding sites on the Hb
• Binds 240 times more strongly to the Hb then oxygen
• When it binds it forms carboxy Hb
• Cells become started for oxygen and death can occur in minutes
• CO found in incomplete burning of natural gas, wood and tobacco. |
|
|
Term
| Carbon Dioxide is transported 3 ways: |
|
Definition
i) In Plasma – 8%
ii) Bound to Hb – (bound to globin) – 20%
iii) Bicarbonate Ions HCO3 |
|
|
Term
| Bicarbonate Ions carbon dioxide transport: |
|
Definition
• Tissue cells produce CO2 CO2 goes into the interstitial fluid then into the plasma, then in to the RBC
• CO2 reacts with the water and an enzyme carbonic anhydrase to form H2CO3 (Carbonic acid). The carbonic anhydrase is found in the RBC.
• H2CO3 is very unstable and begins to dissociate into H+ and HCO-3
• HCO-3 moves out into the plasma.
• Negatively charged Chloride moves in (CL-). Called Chloride Shift.
• RBC have high levels of chloride when the blood is deoxygenated. This blood goes to the lungs |
|
|
Term
|
Definition
• Oxygen moves into the deoxygenated blood from the alveoli
• Oxygen binds to the HbH and Hydrogen is released. Now have HbO2
• Bicarbonate ion (HCO-3) moves back in to the RBC and the chloride moves out. Referred to as the Reverse Chloride Shift |
|
|
Term
See page 862, fig 22.22a for diagram at tissue
See page 862, fig 22.22b for diagram at lung. |
|
Definition
|
|
Term
| Respiratory Centre (medulla oblongata) |
|
Definition
• During quiet breathing the inspiratory centre is active for 2 seconds. Then is becomes inactive for 3 seconds (have expiration)
• This rhythm of breathing is set by the inspiratory centre. If damaged breathing stops
• This process is not well understood. |
|
|
Term
| Pontine Respiratory Centre (in Pons) pg 865 |
|
Definition
• May make the transition between inspiration and expiration smooth and regular. Fine tunes what is happening in the medulla
• If damaged the person would have irregular breathing. Breath in gasps |
|
|
Term
|
Definition
• Found in the bronchi and the bronchioles of lungs
• Functions to prevent lungs from over stretching (reflex)
• This reflex is called Hering-Breuer Reflex – inhibits inspiration |
|
|
Term
|
Definition
• Impulses begin in the primary motor area
• Normally respiration is automatic but we do have voluntary control
Ex: hold breath, breath fast or slow
• Uses the corticospinal pathway |
|
|
Term
|
Definition
– chemical regulation, sensitive to:
• PCO2, PO2, pH (via H+ concentration) |
|
|
Term
|
Definition
• In the medulla oblongata
• Increase in CO2 poorly sensed
• Increase in H+ read and not the CO2 |
|
|
Term
| Peripheral Chemoreceptors |
|
Definition
• Called the carotid bodies
• Main chemoreceptor in the carotid artery |
|
|
Term
| Arterial PCO2 = 40 + 3 mmHg |
|
Definition
• The following is the most powerful stimulus for changes in respiration
- ↑PCO2 (by 5 mmHg out of homeostatic range) ventilation will double |
|
|
Term
| Central chemoreceptors - ↑CO2 (in cerebral spinal fluid) diffuses into the medulla oblongata and reacts with H2O. This results in: |
|
Definition
• Results in an increase of H+ in the medulla.
• The central chemoreceptors in the medulla would pick up on the increase of H+
• Chemoreceptors respond to the CO2 by sensing the increase of H+
• Indirect response |
|
|
Term
|
Definition
• ↓ O2 in the blood can stimulate the peripheral chemoreceptors only sensed when below 60 mmHg
• This is an extreme drop in the PO2 from 100 to 60. O2 is very low
• O2 not sensed by the central chemoreceptors, peripheral chemoreceptors will sense this, but at this point the body is only left with about 4 minutes of oxygen must give emergency O2 |
|
|
Term
| Exercise – Influence on ventilation |
|
Definition
• Poorly understood
• Immediately when a person exercises ventilation increases
• PO2 and PCO2 are normal
• Probably causes:
• 1) Activation of skeletal muscles and respiratory centres
• 2) Proprioceptors in muscles, joints, tendons might be sending impulses to the respiratory centres
• 3) Anticipation of exercise could increase ventilation
• 4) Increase in body temp as you exercise. |
|
|
Term
|
Definition
decrease in the normal rate of ventilation, includes holding breath
• Get build up in PCO2 (not blown off)
• Stimulates the central chemoreceptors (H+) and peripheral chemoreceptors (H+)
• Automatically breath – must breath, have no choice |
|
|
Term
|
Definition
Breathe faster than normal
• Anxiety breathe faster
• Blow off excess amounts of CO2. PCO2 drops
• Drop in H+ concentration
• Cause body to breathe slower
• Dizziness – blood vessels in brain constrict |
|
|
Term
| __1___ pathway involved with breathing, but when breath is held the __2__ takes over and the corticospinal pathway no longer effective. |
|
Definition
1) Corticospinal
2) medulla |
|
|
Term
|
Definition
• The tube from the mouth to the anus
• Also called the gastrointestinal tract (GI) |
|
|
Term
| Accessory Organs – help in digestion |
|
Definition
| • Liver, pancreas, teeth, tongue, gallbladder |
|
|
Term
|
Definition
| • Taking food into the mouth |
|
|
Term
|
Definition
| • Moving food through the digestive tract by swallowing, and peristalsis |
|
|
Term
|
Definition
• Breaking down of large molecules into smaller molecules
• 2 types:
i) Mechanical digestion – chewing food, churning, segmentation (in small intestines)
ii) Chemical digestion – enzymes used to breakdown food – secreted by glands. |
|
|
Term
|
Definition
• End products of digestion enter into the blood or the lymph
• 90% of absorption is in small intestines |
|
|
Term
|
Definition
| • Elimination of undigested food in the form of feces |
|
|
Term
|
Definition
• Proteins
• Produced by transcription/translation
• Speed up rate of reaction by 1010
• Can be released in an inactive form – this form breaks down proteins and is called proteolytic enzymes (proteases) – inactive so they do not breakdown the stomach wall
• Most enzymes end in “ase” – exceptions are pepsin, tropsin
• Must have optimal conditions for enzymes to function body temp 37ºC
• If over 37ºC the enzyme breaks down, below this temp can not function
• Must have optimal pH of 7 (exception – pepsin functions at pH of 2) |
|
|
Term
| Brake down of food in the mouth includes: |
|
Definition
Chemical and mechanical digestion
• Mechanical digestion: chewing – forms a round ball called a bolus
• Chemical digestion: breakdown of polysaccharides by salivary amylase to disaccharides. |
|
|
Term
|
Definition
• Consists mainly of water
• Contains amylase
• Moistens the food
• Functions in taste |
|
|
Term
True or False?
The sympathetic nervous system is the dominant system during digestion? |
|
Definition
flase! the Parasympathetic Nervous System is the dominant system during rest and digestion
• Salivary glands produce watery saliva, rich in amylase
• Secrete about 1 – 1 ½ liters/day of saliva
• During fight or flight, the SNS is dominant, inhibits secretion of saliva |
|
|
Term
|
Definition
• Food moves into the pharynx to the pharyngeal phase
• Walls of pharynx consist of skeletal muscle
• Breathing temporarily stops when swallowing
• Swallowing/deglutition reflex – centred involved in swallowing found in the medulla
• The tongue moves up against the palate to prevent food from moving back into the mouth
• Food is also prevented from moving up into the nasopharynx by the uvula which raises up and seals off this area
• The epiglottis closes off the opening into the larynx to prevent food from entering the respiratory tract |
|
|
Term
|
Definition
• Food moves via peristalsis (contraction of smooth muscles)
• Peristalsis is a function of the PSNS (via the vagus nerve) |
|
|
Term
| Mechanical digestion in the stomach |
|
Definition
• Churning that occurs in the stomach causes the food to mix with gastric juices
• Mixture is called Chyme |
|
|
Term
| Chemical digestion in the stomach |
|
Definition
• Gastric juice – contains HCL and water (pH 2)
• HCl is produced by the parietal cells
• Pepsinogen is produced by the Chief cells and is an inactive enzyme
• Pepsinogen is initially inactive to prevent digestion of the walls of the stomach
• Pepsinogen is activated by HCL to become pepsin (pepsin is active)
• Pepsin digests proteins by breaking down the protein into peptides
Protein Pepsin . Peptides
pH2, 37ºC
• Walls of stomach are protected by secretion of mucus and bicarbonate ions
• Peptides are still too large to be absorbed in the stomach. The stomach can absorb water, electrolytes, aspirin, and alcohol. Generally not a lot of absorption happens in the stomach |
|
|
Term
Regulation of Gastric Juice Secretion
1) Cephalic phase |
|
Definition
• Last minutes
• Stimulus is the thought of food, taste of food and seeing food.
• These can begin the start of secretion of Gastric Juice |
|
|
Term
Regulation of Gastric Juice Secretion
1)Cephalic phase - PSNS |
|
Definition
• Functions to stimulate (via the vagus nerve) stomach glands to secrete gastric juice
• PSNS also releases ACh
• ACh stimulates secretion of hormone called gastrin (hormone). Gastrin also stimulates increase in gastric juice. |
|
|
Term
Regulation of Gastric Juice Secretion
2) Gastric Phase |
|
Definition
• Can last 3 – 4 hours
• Stimuli include – food present in stomach, extension of stomach, drop in pH |
|
|
Term
Regulation of Gastric Juice Secretion
Gastric Phase - PSNS |
|
Definition
PSNS
• Stimulates production of gastric juice
• PSNS G cells gastrin
Alcohol/coffee can cause release of gastric juice secretion. |
|
|
Term
| Intestinal Phase (3 steps) |
|
Definition
• Food enters the duodenum of small intestine
• The acid chime is the stimulus in the duodenum
i) Excitatory component:
• Small amount of acid chyme enters duodenum, goes to the stomach causing it to increase gastric juice.
ii) Inhibitory component:
• Enterogastric reflex – reflex from small intestine to stomach which inhibits gastric secretion. Also stimulates the SNS and inhibits the PSNS to the stomach, causing a decrease in the production of gastric juice, and prevents churning
iii) Secretion of hormones
• Secretin and Cholescystokinin (CCK) – both inhibit gastric juice secretion
• Endocrine cells of the intestine secrete the above 2 hormones |
|
|
Term
|
Definition
• Has duct that opens into the duodenum
• Produces pancreatic juice
• Pancreatic juice has an alkaline portion and enzymes |
|
|
Term
| Alkaline secretion of the pancreas |
|
Definition
– stimulated by secretin
• Produced by the duct cells (duct from the pancreas to the duodenum)
• Neutralizes the HCL. Secretion contains bicarbonate ions
• HCl + HC0-3 H2CO3 (carbonic acid (weak) – produces less H+ ions then HCl |
|
|
Term
|
Definition
– produced by the acinar cells in the pancreas
Pancreatic Enzymes Amylase (CHO digestion)
Lipase (fat digestion) |
|
|
Term
|
Definition
– digest protein (three types)
• Trypsinogen activated by enteropeptidase to become trypsin
• Chymotrypsinogen activated by trypsin to become chymotrypsin
• Procarboxypeptidase activated by trypsin to become carboxypeptidase
Production of proteases and enzymes stimulated by CCK. |
|
|
Term
|
Definition
• Produces bile
• Production of bile is stimulated by the PSNS/Secretin
• Also have bile pigment which are produced by the pigment from RBC breakdown
Bile contains water, bile salts (produced from cholesterol) |
|
|
Term
|
Definition
| • Fats are large globules in the intestines. Bile salts breakdown the fat into little droplets. |
|
|
Term
|
Definition
| – required for fat absorption |
|
|
Term
|
Definition
• Stores and concentrates bile
• When stimulated by CCK the walls of the gall bladder contract and release the bile into the duodenum |
|
|
Term
|
Definition
| • Uses mechanical digestion and enzymes in small intestine to digest all three food groups – carbohydrates, protein, and fats |
|
|
Term
| Mechanical digestion of the small intestine |
|
Definition
• Peristalsis – contraction of the smooth muscle moves food along the small intestine
• Segmentation – contraction moves the food back and forth to allow some digestion. Segmentation happens only in the small intestine |
|
|
Term
| chemical digestion of the small intestine |
|
Definition
• Acid chyme enters duodenum
• Enzymes in the small intestine function at pH of 7 so the acid chyme must be neutralized
• Neutralized by bicarbonate alkaline solution
• HCl (pH 2) + HCO-3 H2CO3 (carbonic acid – weak acid close to pH 7) |
|
|
Term
| Absorption in the small intestine |
|
Definition
• In the villus are blood vessels and lymphatic vessels (close to the epithelial cells)
• 90% of absorption occurs in the small intestine
• Monosaccharides – enter first into the epithelial mucosa cells by active transport or facilitated diffusion. Then move out from the mucosal cells into the blood by facilitated diffusion.
• Amino acids enter into the epithelial cells by active transport, enter blood by facilitated diffusion
• Fatty acids and monoglycerides
i)Short chain fatty acids
• Less then 12 carbons in its structure
• Fat soluble so they go into the cell by simple diffusion and then into the blood by simple diffusion. |
|
|
Term
| Digestion of a long chain of fatty acids in the small intestine: |
|
Definition
Long chain fatty acids & monoglycerides (fig 23.36, p 932)
• More then 12 carbons in structure
• Any fat soluble vitamins (A, E) also transported
• Associated with bile salts and form the micelle in the lumen of the small intestine Fatty acids/monoglycerides + Bile salts
• Micelle functions as a ferry. Ferry the long chain fatty acids into the cell membrane of the epithelial cells
• Once the micelle gets to the epithelial cell it diffuses into the epithelial cell. The bile sales remain in the lumen (eventually will be reabsorbed and re-cycled) |
|
|
Term
| Inside the Epithelial Cell of the small intestine |
|
Definition
• 2 fatty acids interact with the monoglycerides to form a triglyceride. The triglyceride is coated with a protein to form a structure called a chylomicron (lipoprotein)
• Chylomicron diffuses into the lacteal. Lacteal is a lymphatic capillary. Chylomicron will become part of the lymph system (makes lymph look white)
• Lymph flows into the thoracic duct and drains into the left subclavian vein |
|
|
Term
|
Definition
• Food residue (not absorbed in small intestine)
• No digestion in the large intestine
• Absorption of water from food residue
• Ions also absorbed with the water
• Get synthesis of some vitamin B and K. Done by the bacterial in the large intestine |
|
|
Term
| Haustral contraction (large intestine) |
|
Definition
– pouches on the large intestine
• Slow contractions – 2 per hour. Allows the absorption of water back onto the blood. Also allows the bacteria to flourish |
|
|
Term
| Peristalsis (large intestine) |
|
Definition
| – slower then the peristalsis in the small intestine |
|
|
Term
| Mass Peristalsis (large intestine) |
|
Definition
– for mass movements
• Powerful contraction which begins in the middle of the transverse colon. Pushes the contents into the rectum. Initiated by reflex called gastrocolic reflex (stimulus – food entering the stomach) |
|
|
Term
| Rectal Reflex (large intestine) |
|
Definition
(defecation reflex) – eliminates feces from the rectum
Reflex Arc:
• Stimulus – feces enters the rectum
• Receptor – stretch receptors
• Nerves from the sacral segments stimulate the effector
• Effector – smooth muscles of the internal sphincter relaxes. We voluntarily relax the external sphincter muscles in order to eliminate the fecal matter. |
|
|
Term
| Fate of absorbed Monosaccharides (Glucose) |
|
Definition
• Move from the blood into the body cells by facilitated diffusion. Insulin is required except for the brain.
• Glucose in the cell of the body is used for the following:
a) Anabolism – produce glycogen (storage carbohydrate)
80% stored in skeletal and cardiac muscles
20% stored in the liver
b) Catabolism – production of ATP by cellular respiration
Glycogen is only 1% of the body’s stored energy (not a lot stored) |
|
|
Term
|
Definition
• Fatty acids, cholesterol and triglycerides
• Diffuse from blood into the body cells
• Both long and short change fatty acids diffuse into the body cells
• Used for the production of ATP
• Used for the synthesis of phospholipids, myelin, steroid hormones and bile salts.
• Most lipids stored in the subcutaneous layer of the skin and in the kidneys
• Lipids are 99% of the body’s stored energy |
|
|
Term
|
Definition
(from protein)
• Enter into the body cells by active transport
• Need insulin and growth hormones to get into the body cells
• Amino acids used to synthesize other proteins (ex enzymes, collagen, hormones, etc)
• Amino acids used to synthesize ATP only in starvation and marathon runners |
|
|
Term
|
Definition
- the body’s use of energy within a given time period.
• Looks at all chemical reactions and any mechanical work (ex: contraction of muscles) |
|
|
Term
| Factors that influence Metabolic Rate: |
|
Definition
1) SNS – when dominant functions to increase the metabolic rate.
2) Hormones
• NE and E – increase because of the SNS
• Thyroxin – major affect on the metabolic rate. Called the metabolic hormone.
3) Body temperature – When body temperature increases above homeostasis the metabolic rate also increase (increase of 10% when the body temp goes up one degree). When the temperature drops below homeostatic range the metabolic rate also increases.
4) Exercise – increases the metabolic rate
5) Food digestion – increase the metabolic rate
6) Sleep – metabolic rate decreases during sleep |
|
|
Term
| Basal Metabolic Rate (BMR) |
|
Definition
| - the slowest metabolic rate required to sustain vital functions. Measured under controlled and standardized conditions (prevents other factors from affecting it). |
|
|
Term
| To correctly measure the BMR the following conditions must be adhered to: |
|
Definition
i. Fast for up to 12 hours
ii. Body temperature must be normal
iii. Person must be resting and awake
iv. No exercise
v. Room temperature must be controlled. |
|
|
Term
|
Definition
• Cortex: Medulla and minor and major calyces
• Pelvis: Ureters; Urinary bladder |
|
|
Term
|
Definition
| • Bowman’s capsule; proximal and distal convoluted tubules; loop of Henle (ascending and descending limbs); collecting duct |
|
|
Term
| Blood Supply to the kidneys |
|
Definition
• Afferent arterioles; glomerulus
• Efferent arterioles; peritubular capillaries (cortical), peritubular and vas recta (juxtamedullary) |
|
|
Term
| Juxtaglomerular Apparatus |
|
Definition
| • Juxtaglomerular cells on afferent arterioles and macula densa cells on the distal convoluted tubule |
|
|
Term
| Filtration Membrane of the kidney |
|
Definition
• Endothelium on the glomerulus
• Podocytes on the bowman’s capsule |
|
|
Term
|
Definition
• Regulate water balance and plasma volume
• Directly regulate blood pressure
• Function to regulate ion concentration in the blood regulates the pH of blood (through H+ ion concentration)
• Gets rid of toxic substances in the body
• Gets rid of food additives and drugs
• Produces hormone called Erythropoietin
• Erythropoietin is secreted when oxygen levels in the blood are low (low PO2 erythropoietin is released and goes to the bone marrow to stimulate the production of more Red blood cells.
• Release of renin when the blood pressure is very low (renin causes the conversion of angiotensin into angiotensin II) |
|
|
Term
| Urinary Production (3 processes involved) |
|
Definition
1) Glomerular Filtration
2) Tubular Reabsorption
3) Tubular Secretion |
|
|
Term
|
Definition
• Filtration from glomerulus into the bowman’s capsule
• Get bulk flow – water with dissolved solutes passes through to the Bowman’s capsule, but proteins are too large to pass through so they stay in the blood.
• Fluid that goes into the Bowman’s capsule is called filtrate. Everything but protein. |
|
|
Term
|
Definition
| • The movement of water and solutes from the filtrate into the peritubular blood vessels and the vasa recta |
|
|
Term
|
Definition
| • Certain substances (includes K+ and H+) move from the peritubular/vasa recta into the filtrate |
|
|
Term
|
Definition
- NFP (this creates the bulk flow)
• 3 pressures involved in transfer from plasma to bowman’s capsule
i. Glomerular Hydrostatic Pressure (GHP). This is the blood hydrostatic pressure in the capillary
ii. Capsular Hydrostatic Pressure (CHP). Pressure from bowman’s capsule into the capillary
iii. Blood Osmotic Pressure (BOP). Pulls fluid into the capillary |
|
|
Term
| Regulation of the Glomerular Filtration Rate (GFR) |
|
Definition
• Regulated by regulating the GHP
• If ↑MAP get ↑GHP. If this is not regulated we will get an increase in the GFR. GFR must be maintained at a constant level. |
|
|
Term
| Autoregulation / Intrinsic Regulation of glomerulra filtration |
|
Definition
• Regulates the diameter of the afferent arteriole (major mechanism under normal conditions)
A) Change in MAP
↑MAP get ↑ GHP, but if the MAP increases the afferent arteriole constricts. The GHP remains steady (get ↓GHP).
↓MAP get afferent arteriole dilation so the GHP ↑.
• The above two methods work to keep the GFR steady
• Smooth muscles sense “stretch” so they constrict or if the flow drops the muscles will dilate the vessel
B) Kidneys sense a change in flow of the filtrate
Macula densa cells pick up change in flow of filtrate.
↑GFR indicates an increase in flow of the filtrate. The macula densa cells would secrete a chemical that would cause the afferent arterioles to constrict. |
|
|
Term
| extrinsic control og Glomer Filration |
|
Definition
Under extremely low blood pressure
Ex: Hypovolemic shock, sweating (causing decrease in fluid in the blood)
• ↓Blood flow results in a decrease in MAP stimulates the SNS
• The SNS would send impulses to the arterioles and would constrict both the afferent and efferent arterioles causing a drop in GFR
• Get decrease in volume of urine produced. Blood retains the water to keep blood volume higher
• Also have release of Renin from walls of the afferent arteriole causing an increase in angiotensin II (this causes a massive vasoconstriction
• Aldosterone also secreted – increases blood volume
• ADH released (from posterior pituitary) causing vasoconstriction |
|
|
Term
|
Definition
• BOP is due to the large proteins in the blood. When we eat salty foods, the salt goes into the blood increasing the BOP.
• When the BOP increases this is going to cause a decrease in GFR (produce more concentrated urine because of less water being released) |
|
|
Term
|
Definition
| • At the capillaries we get proteins passing though because the cells of the capillaries have spread out. Proteins enter the filtrate resulting in a drop in BOP. We then get an increase in GFR |
|
|
Term
|
Definition
| • Blockage down urinary tract (stones in the ureters/ enlarged prostrate) create back pressure. The CHP increase – more fluid moves from filtrate into the blood and the GFR decreases |
|
|
Term
| Proximal Convoluted Tubule |
|
Definition
• Glucose and amino acids (99% of what is filtered) is reabsorbed (back into peritubular capillaries)
• Reabsorb sodium chloride (NaCL) – 66% reabsorbed
• Reabsorption of small proteins and vitamins
• When these are added back the BOP increases, causes water also to go from the filtrate to the blood (also adds to the increase of BOP)
• This draws water toward the bllod. This is called “Obligatory Reabsorption of H2O”
• 66% of H2O reabsorbed
Result of solute and water – get decrease in volume of the filtrate. Contains large amounts of solute
• Concentration of filtrate is 300mOsm/Litre
• Interstitial fluid will also have a concentration of 300 mOsm |
|
|
Term
|
Definition
Descending Limb:
Water is diffusing out (very permeable to water) goes into the interstitial fluid then into the vasa recta. Filtrate becomes more concentrated. |
|
|
Term
|
Definition
| • Not very permeable to water. Not water leaves at this point |
|
|
Term
|
Definition
• Not very permeable to water
• Concentration remains at 100 mOsm/litre in the collecting duct |
|
|
Term
| Nitrogenous Waste Products in the Urine |
|
Definition
• Protein and amino acid metabolism – end product is urea. This is a toxic substance
• 50% of it is reabsorbed so there must be constant filtration
• Nucleic acids broken down – end product is uric acid. 10% of uric acid is secreted
• Creatine metabolized get creatinine. Creatinine is filtered from the blood and is secreted from the blood into the filtrate in constant amounts. No reabsorption. This is test for in the blood. If levels are high then this can indicate problems with the kidneys |
|
|
Term
| proteinuria or albuminuria glomerulonephritis |
|
Definition
Excessive protein/albumin (abnormal)
• Caused by high blood pressure |
|
|
Term
|
Definition
Excessive glucose caused by:
i) High Carbohydrate Diet – if there is an excessive amount of glucose it may not be reabsorbed
ii) Intravenous Glucose – can cause presents of glucose in the urine
iii) Stress – causes a decrease in the secretion of insulin so the glucose levels will remain high in the blood. |
|
|
Term
|
Definition
Stimulus - Urine into bladder (stretching)
Receptor - stretching of walls of the bladder, stretch receptors
Control centre - spinal cord reflex (PSNS)
Effector - detrusor muscle, internal sphincter relaxes, external sphincter relaxes voluntarily |
|
|
Term
| Regulation of Urine Concentration (see fig 25.13) |
|
Definition
| When the kidney is regulating solute concentration and the urine, this is actually regulating the concentration and volume of blood. |
|
|
Term
Regulation of Urine concentration
Counter |
|
Definition
– current multiplier mechanism
• An osmotic gradient is produced by the solute going back into the medulla and cortex. Medulla more salty then the cortex.
• This gradient results in water moving back into the blood. Water is coming from the collecting duct
• This will result in the production of a concentrated urine
• This is the function of the Juxtamedullary nephons
• Counter-current – means that the flow of the filtrate is moving in opposite directions and the loop of henle is close to the blood flow.
• Multiplier – sodium chloride is pumped out the ascending limb, but that salt remains in the medulla, so it becomes saltier.
• Water – in descending limb water moves out by osmosis and into the vasa recta. This water does not remain in the medulla, but ends up back in circulation. |
|
|
Term
| Verticle Osmotic Gradient in the Kidneys |
|
Definition
• See fig 25.13
• Gradient produced by the loop of henle and the vasa recta
• In the cortex NaCL is picked up by the blood. NaCL in the medulla remains in the medulla
• This gradient allows the collecting duct to produce a concentrated urine. |
|
|
Term
| Production of a Dilute Urine |
|
Definition
• Have increase in volume of water in the urine
• Produced by an excess amount of water in the blood
• If person has high blood pressure, also cause production of dilute urine
• When the filtrate enters the collecting duct it ahs a concentration of 100 mOsm/litre. Nothing will happen in the collecting duct. Contents of the filtrate stay the same. When the filtrate leaves the collecting duct it be is now called urine. |
|
|
Term
| Production of Concentrated Urine |
|
Definition
• Decrease in volume of water, but the same amount of solute
• Produced under conditions of dehydration, or low blood pressure
• Hormone ADH is secreted from the posterior pituitary gland (ADH prevents fluids from being released from the body via urine)
• ADH causes the distal convoluted tubule and the collecting ducts to become more permeable to water. This means more water passes through and moves out to the interstitial fluid and then moves back into circulation
• Channels open up in the cells and water moves out because of the concentration gradient. This is called “Facultative Reabsorption of Water”
• If ADH is secreted to its maximum, the filtrated water can have a 99% reabsorption rate.
• Formation of concentrated urine is dependant on ADH and the vertical osmotic gradient.
• Primary function of the juxtamedullary nephron |
|
|
Term
Regulation of Urine Concentration
ADH |
|
Definition
- produced in the posterior pituitary
• Secreted into blood if blood pressure is low, or we have dehydration
• Regulates permeability of the Distal convoluted tubule and collecting duct
• Responsible for “Facultative reabsorption of water”
• When the amount of water released as urine decreases, the water goes back into the blood
• Water and alcohol decrease ADH secretion
• Water and alcohol cause a dilute urine to be produced |
|
|
Term
Regulation of Urine Concentration
Angiotensin II |
|
Definition
• Secreted when blood pressure is low and blood volume is low
• Also secreted if blood Na+ is too low, or K+ is too high
• Will constrict all arterioles, especially the afferent and efferent arterioles. Causes a decrease in the amount of filtration
• Angiotensin II will also stimulate the production of ADH |
|
|
Term
Regulation of Urine Concentration
Aldosterone |
|
Definition
• Also stimulated by Angiotensin II
• Aldosterone is also released if K+ is too high in the blood
• Regulates the reabsorption of Na+
• Regulates the secretion of K+
• For every Na+ picked up, one K+ is secreted. This occurs in the distal convoluted tubule and collecting duct.
• Na+ goes into the peritubular capillaries from the collecting duct, water also flowing out. We get a concentrated urine |
|
|
Term
| Atrial Natriuretic Peptide |
|
Definition
• Released in response to blood pressure being too high
• Increases the excretion of sodium
• Also functions to inhibit secretion of ADH
• Filtrate is excreted as dilute urine
• Prevents water from being added to the blood
Atrial Natriuretic Peptide
• Released in response to blood pressure being too high
• Increases the excretion of sodium
• Also functions to inhibit secretion of ADH
• Filtrate is excreted as dilute urine
• Prevents water from being added to the blood |
|
|
Term
Regulation of Urine Concentration
SNS |
|
Definition
• Dominant during exercise, fight or flight response, and dehydration
• Afferent arterioles constrict – decrease of glomerular filtration, get less filtration and less urine. |
|
|
Term
|
Definition
Renal plasma clearance – the rate that a substance is completely removed (cleared) from the plasma. This substance is removed by the kidneys.
i) Gives information about the glomerular filtration rate (GFR)
• Indicates volume of filtrate produced per minute
• Important to know for the use of drugs
ii) Also tells if kidneys are not functioning properly
• A plant derived substance known as inulin is used to determine GFR.
• Inulin is a carbohydrate and would be injected into the blood. It is filtered out, not reabsorbed, not secreted and not metabolized. Goes to the kidneys for removal.
• PC (plasma clearance) = GFR = 125ml/min
• In 1 minute the kidneys will have removed all of the inulin in 125 ml of plasma |
|
|
Term
| Values less then 125 ml/min PC |
|
Definition
Substance is filtered and reabsorbed
Ex: Urea – 70 ml/min
Glucose – 0 ml/min (100% reabsorbed) |
|
|
Term
| Values more than 125 ml/min PC |
|
Definition
Substance is filtered and secreted
Ex: H+ = 150 ml/min
Creatinine = 140 ml/min |
|
|
Term
|
Definition
• H+ concentration can be affected by diet (protein consumption, metabolism)
• 3 mechanisms in place to regulate the pH of the blood. Prevents drastic changes in pH. |
|
|
Term
| Buffering System in the Blood |
|
Definition
Combination of the following creates the buffering system:
• Weak acid – release H+ when combined with water
• Weak base – binds free H+
• Major buffering system in the blood is made up of weak acid and weak base
• Excess H+ react with the bicarbonate to produce a weak acid (carbonic acid) |
|
|
Term
Maintaining pH in blood
Lungs |
|
Definition
• Acts within minutes to restore the pH.
• Excess H+ Stimulates the peripheral chemoreceptors ↑ventilation
• When the ventilation increases the lungs will blow off more CO2:
H+ + HCO-3 H2CO-3 CO2 + H2O
• By eliminating CO2 reaction reverses and get less H+. This removes H+ from the blood and puts it back into homeostatic range.
• Lungs take care of about 70% of this imbalance. |
|
|
Term
Regulation of pH in the blood
Kidneys |
|
Definition
• Eliminates H+ from the acids. Done in 2 ways:
a) Increasing the secretion of H+
b) Increasing the reabsorption of Bicarbonate ions (HCO-3). The HCO-3 will go back into the blood and become part of the buffering system.
In plasma there is a ratio of HCO-3 to CO2 = 20 : 1
This ratio must be maintained to keep the blood pH level in the normal range. The lungs and the kidneys function together to maintain this ratio. |
|
|
Term
|
Definition
– increase in H+ concentration in plasma.
• PH will be less then 7.35. Up to 7.0 we can function, but at 6.8 death.
• This situation depresses the CNS (brain and spinal cord). Can go into a coma, heart rate becomes irregular, blood vessels dilate, and enzymes can not function. |
|
|
Term
|
Definition
• Malfunctioning of the lungs – referred to as Hypoventilation (slower then normal). Causes of respiratory acidosis are emphysema, damage to the respiratory center in the medulla oblongata, damage to the diaphragm.
• Get an increase in PCO2 which results in an increase in H+
• If lungs are damaged they can not compensate so the work would go to the kidneys.
• The kidneys would increase secretion of H+ and increase reabsorption of HCO-3. |
|
|
Term
|
Definition
• Caused by extreme diarrhea resulting in loosing too many HCO-3 ions. (Less HCO-3 available for the blood).
• Ex: Diabetes Mellitus – when glucose can not get into the cells we get an increase in fat metabolism. This results in increased levels of acids such as keto acids and lactic acid.
• Metabolic acidosis can also be caused by renal/kidney failure
• Lungs will try to compensate by increasing ventilation ↓PCO2 ↓H+
• If the kidneys are functioning they would ↑H+ and ↑ reabsorption of HCO-3 |
|
|
Term
|
Definition
• Increase in HCO-3 in the plasma
• Higher then pH of 7.45 (over 7.8)
• If it goes up to a pH of 8, person can die
• Results in over excitation of the CNS (convulsions)
• Breathing muscles go into spasms (cause of death) |
|
|
Term
|
Definition
• Hyperventilation – ↓PCO2 results in ↓H+. Get more HCO-3
• If lungs are functioning they will compensate by decreasing ventilation ↓PCO2 ↓Ventilation results in ↑PCO2
• If the lungs are not functioning the kidneys will decrease secretion of H+ also decrease reabsorption of HCO-3 |
|
|
Term
|
Definition
• Caused by excessive vomiting - loosing too much gastric juice (HCL)
• Caused by using to many tums (cause excessive amounts of HCO-3
• Lungs can compensate by decreasing ventilation (increases amount of PCO2 which results in more H+)
• Kidneys will decrease secretion of H+ and decrease reabsorption of HCO-3 |
|
|
