-excited

-motor neuron

The least amount of muscle cells that can be excited is

The largest amount of muscle cells that can be excited is

An example of part of the body...

With few muscle cells?

With many muscle cells?

-eye

-hammy

1. excitation

2. excitation-contraction coupling

3. contraction

4. relaxation

During muscle excitation:

there is communcation between the _________ and _______ _____.

During excitation-contraction coupling:

conversion of _____ ____ in muscle to ________ of protein in the _______

During contraction:

-muscles develop _____ and may _____

-_________ _____ theory

-tension/shorten

-sliding filament

During relaxation:

-return to _______

Excitation (steps 1 and 2)

-_____ _____ from motor neurons reaches ____ __ _____

-_____ gated _____ channels ____

-____ enters the neuron and causes _____ ______ to release ____.

-action potential/end of axon

-voltage/calcium/open

-calcium/synaptic vesicles/ACh

Excitation (3 and 4)

-ACh binds to _____ in the ______ ________

-Receptors are ______-gated, dual ______/______ ion channels

-receptors/motor plate

-chemically/sodium potassium

Excitation (steps 3 and 4)

-_____ rushes into the cell ->_____

-______ leaves the cell ->_______

-net result is ____ because?

-sodium/depolarization

-potassium/repolarization

-depolarization because more sodium enters than potassium leaves

Excitation (steps 3 and 4)

The net result of depolarization (more sodium leaving) is called?

Excitation (step 5)

-Depolarization of EPP causes potential to reach _____, which causes for an _____ _____

-______gated, ___ channels open on motor plate

-threshold/action potential

-voltage/sodium (Na+)

Excitation-Contraction Coupling (steps 6 and 7)

-action potential travels across the ____ ______ and (up/down) _______

muscle membrane

down

T-tubules

Excitation-Contraction Coupling (steps 6 and 7)

-_____gated ____ channels in Ttubules are _____ linked to ____ ion channels in the ______ ____

-voltage/sodium/physically/

calcium/sarcoplasmic reticulum

Excitation-Contraction Coupling (steps 6 and 7)

-Action potential triggers _____ channels to ____, _____ _____ channels also open

-calcium enters the ____ of the muscle cell

-sodium

open

SR calcium

-cytoplasm

Excitation-Contraction Coupling (steps 7 and 8)

-_____ released by SR binds to ____

-Troponin-tropomyosin complex changes ______ and exposes ____ ____ on thin filaments (actin)

-calcium/troponin

-shape/active site

Contraction(steps 10 and 11)

What hydrolyzes an ATP molecule?

Contraction(steps 10 and 11)

-What is produced when myosin hydrolyzes an ATP molecule?

Contraction(steps 10 and 11)

-The hydrolizing of ATP activates the head in what kind of position?

Contraction(steps 10 and 11)

Where does myosin bind to?

Contraction(steps 10 and 11)

What is formed when myosin binds to the actin active site?

What is still bound?

a cross bridge between actin and myosin

-ADP+P

Contraction (steps 12 and 13)

The interaction of cross-bridge causes?

Contraction (steps 12 and 13)

The release of ADP and P causes:

-head to ____

-____ filament to slide past the _____

-flex

-thin/thick

Contraction (steps 12 and 13)

What must bind to myosin to release the head?

Contraction (steps 12 and 13)

Once ATP binds to myosin to release head:

-immediately ______

-some heads are always bound to prevent ______

-hydrolyzes

-slippage

Contraction (steps 12 and 13)

thin and thick filaments do not become shorter, so what happens?

Rigor Mortis..

As the body deteriorates, what is released from the SR?

Calcium:

-bind _____

-moves _______

-allow ______ to bind

-troponin

-tropomyosin

-myosin

After death, ATP is no longer made

true or false

Sarcomeres will stay in contracted state when death occurs?

true or false

Relaxation (14 and 15)

During relaxation, what ceases and why?

Relaxation (14 and 15)

During relaxation, ACh breaks down thanks to?

Relaxation (14 and 15)

acetylcholineseterase is an...

Relaxation (14 and 15)

Once products are broken down by AChE, what happens?

During relaxation, no EPP (or action potentials) are produced in the muscle membrane

true or false

Relaxation (step 16)

What is needed to pump calcium back into SR?

Relaxation (step 16)

Active transport pumps what back into SR?

Relaxation (step 16)

Active transport doesn't use ATP

true or false

Relaxation (steps 17 and 18)

Binding of ATP to myosin causes dissociation from ?

Relaxation (steps 17 and 18)

What has to bind in order to dissociate actin?

Relaxation (steps 17 and 18)

What covers active sites in relaxation?

Relaxation (steps 17 and 18)

troponin-tropomyosin complex covers active sites:

-due to lack of _____

-_____ cannot bind

-stops the production of maintenance of _______

-calcium

-myosin

-tension

Relaxation (steps 17 and 18)

During relaxation, sarcomeres return to?

Relaxation (steps 17 and 18)

What returns to resting length?

Relaxation (steps 17 and 18)

A complete cycle is called a...

Stronger impulses from brain

-result in more ___ ____ contracting

-_______ contraction

motor units

stronger

Cardic Muscle Tissue

-Electrical signals spontaneously start at _______ _______.

-sinoatrial nose (SA node)

-atrioventricular node (AV node)

Cardiac muscle cells can excite each other

true or false

Cardiac muscle cells can excite each other due to structures called

Intercalated Discs

Two different types of junctions:

1) mechanical junctions

2) electrical junctions

Entercalated discs

Mechanical junctions

-__________ -> cell adhesion proteins

-allows muscle cells to pull on each other without ______ ______

-desmosomes

-damaging membrane

Intercalated Discs

Electrical junctions are also called...

Intercalated discs

proteins that are non-specific, leaky ion channels

Intercalated discs

Electrical junctions

-allows _____ to diffuse between cells during _______

-_________ of signal

-sodium/depolarization

-propagation

1) provide structrual support for the heart

2) gives the muscle cells something to pull against

3) electrical insulator, helps regulate beating of heart

1)heart pumping blood

2)pulmonary circuit

3) systemic circuit

4)normal flow of blood

heart pumping blood

-deliver _____/____ to all parts of the body

pulmonary circuit

-blood to _____ only

-pick up _____

lungs

oxygen

systemic circuit

-_____ to rest of body

-drop of _____

blood

oxygen

normal flow of blood:

______ -> ______ -> _____

how does blood blow to get back to the heart?

________->_________->_______

-superior and inferior vena cava

-pulmonary arteries

-pulmonary veins

-aorta

Right atrium

left atrium

right ventricle

left ventricle

Which chambers are thin walled?

Blood Flow

________ -> _________->______

Atria

-superior and inferior ___ ___ (from ____) -> ____ _____

-________ veins (from _____) -> _____ ____

vena cava/body/right atrium

pulmonary veins/lungs/left atrium

Valves

-right atria pumps blood through ____ __ ______(______) to ventricle

-left atria pumps blood through ____ ___ _______ (_____) to  ventricle

right AV valve (tricuspid)

left AV valve (bicuspid)

Ventricles

-Right ventricle -> _____ ____ (to __)

-left ventricle -> _____ (to ____)

pulmonary trunk (to lungs)

aorta (to body)

Cardiac tissue action potential has a sodium, potassium voltage-gated channel mechanism?

true or false

Sinoatrial (SA) node

Atrioventricular (AV) node

SA node

-specialized group of cells in the ___ ___.

-cells do not have a ____ ____ ____ ____.

-"______" membrane channels

-____ ____ after action potential redistributes ions

right atria

stable resting membrane potential

leaky

active transport

AV node

-_______ gateway to the ______

-ventricles are otherwise _______ by the _______ _____

electrical/ventricles

insulated/fibrous skeleton

Atrioventricular bundle

-collection of _____

-a.k.a. ____ __ _____

-pathway the ______ signal follows as it leaves the ____ node

-splits into ____ and ____ bundles

cells

bundle of His

electrical/AV

right and left

Purkinje fibers

-collection of _____

-spread throughout the ______

-coordinate ______ of the ______

-because of the _____ of the bundles, ________ contract from the bottom _____

cells

ventricles

contraction/ventricles

direction/ventricles/upwards

-cell of the SA node triggers an action potential

-action potential moves through the two atria causing contraction (also called atria systole)

precedes

milliseconds

ions

action potential

P wave

QRS

T wave

Pressure gradients:

the differences in pressure between ____ points.

Heart beat

5 phases

1) quiescent period

2)atrial systole

3) isovolumetric contraction

4) ventricular ejection

5) isovolumetric relaxation

Phase 1

-atria/ventricle are in _____

-pressure of blood in _____ is higher than pressure in ______.

diastole

vessels/heart

Phase 1

There is no pressure in the _____. So, AV valves are _____.

ventricles

open

Phase 1:

Pressure is higher in _____.

Phase 1:

blood fills _____ and flows through the __ valves to the ______

Phase 1:

The heart fills with blood from the _____ ___.

Phase 1:

How much blood is leftover from previous contraction?

Where is it located?

60mL

ventricle

Phase 1:

Since the capacity of the ventricle is not full, what percentage is full, and how much is it in mL?

75%

90mL

Part 2: Atrial Systole

-the SA node __________

-triggers _____ ____ across the ____

depolarizes

action potentials/atria

Phase 2:

-the atria _____ (in _____ )

-pressure is greater in the ____ compared to the ______.

contract/systole

atria/ventricles

Phase 2:

more blood is _____ into the ventricles.

how much  more? what is the total?

forced

40mL

90mL + 40mL = 130mL

Phase 2:

When is the end of diastolic volume?

Phase 2:

As the ventricles completely fill, what happens?

Phase 3: Isovolumentric contraction

-the atria _____ and ____ (in _____)

-begin ______.

repolarize/relax/diastole

refilling (coming in from blood vessels)

Phase 3:

-ventricles _____ and begin to _____ (in _______)

-contract from _____ up

-blood forces ___ valves closed

depolarize/contract/systole

bottom

AV

Phase 3:

What makes first heart sound?

Phase 3:

pressure ______ in the ventricle

Phase 3:

Why does the blood not leave the ventricles right away?

Phase 3:

no change in volume of blood is called...

Phase 4: Ventricular ejection

-ventricles fully ______ (in _____)

Phase 4

Pressure in ventricles is _____ then pressure in vessels

-forces ______ and ____ valves to open

-blood leaves the ______

-only ___mL of blood leaves

-referred to as ______ _____

greater

pulmonary/aortic

ventricle

70

stroke volume

Phase 4:

How much blood is left behind after stroke volume leaves?

Phase 4:

Once the stroke volume leaves, what is it the end of?

Phase 4:

Atria is still in _______ after end of systolic volume

-continue to ____ with blood.

diastole

fill

Phase 5: Isovolumetric relaxation

ventricles ______ and ______ (in ______)

repolarize/relax/diastole

Phase 5:

Pressure ____ in ventricle

-pressure in pulmonary artery and aorta is ________

-blood tries to flow back, but valves ____ and _____ this

decreases

greater

shut/prevent

Phase 5:

What makes the second heart sound?

Phase 5:

Both sets of valves are still _____ so volume of blood in ventricles ____ ____ _____.

-___________ relaxation

closed/does not change

isovolumetric

Phase 5:

Once atria are filled, ____ valves are forced ____ and ____ begins

AV

open

cycle

End Diastolic Volume (EDV) - End Systolic Volume (ESV)

about 130mL - about 60mL = about 70 mL

4-6 liters

(women have less)

Motor neurons of the sympathetic and parasymphathetic nervous sytem affect heart rate?

true or false

what is the maximum heart rate?

or the limit of SA node excitation?

ACh allows ______ to leave the cell --> _____ reaction

rate of action potentials ______

potassium/hyperpolarizing

decrease

What is the normal heart rate?

What would the heart rate be without nervous control?

70 b/m

about 100 b/m

Preload

-stroke volume is _______ to final ventricular volume

-If more blood is forced into the ventricle (during exercise), the ventricle ______

-results in great _____

proportional

stretches

contraction

Afterload

- What reduces the stroke volume?

-_______ of ventricles is indications of ____ ___ _____.

higher blood pressure

hypertrophy/high blood pressure

What information is integrated in deciding heart rate?

1) sensory input

2) proprioceptors

3) baroceptors

4) chemoreceptors

proprioceptors

-____ brain of change in _____ activity

-increases _____ ____ before ______ demand

inform/physical

heart rate/metabolic

baroceptors

-sense _____ in ____

-pressure too high, _____ heart rate

-pressure to low, _____ heart rate

pressure/vessels

lower

increase

chemoreceptors

-sensitive to ___ of blood

-import in ______ system, has has some affect on ______ _____

-too much _____ ____ (waste), increase heart rate to _______.

pH

respiratory/heart rate

carbon dioxide/remove