Shared Flashcard Set

Details

Chapter 19 (VPHY 3100)
Chapter 19 (VPHY 3100)
190
Physiology
Undergraduate 3
10/11/2020

Additional Physiology Flashcards

 


 

Cards

Term
essential amino acids and examples of them
Definition
-amino acids we need, but can't produce
-lysine, methionine, valine, leucine, isoleucine, tryptophan, phenylalanine, and threonine (lys, met, val, leu, ile, try, phe, thr)
Term
essential fatty acids and examples of them
Definition
-fatty acids we need to obtain from food
-omega-6 and omega-3
Term
some examples of water soluble vitamins
Definition
-Thiamin (B1) -riboflavin (B2) -Niacin (B3) -Pyridoxine (B6) -Vitamin C
Term
the role of water-soluble vitamins
Definition
coenzymes, widespread effects, cannot be stored in the body
Term
the role of Thiamin (B1)
Definition
needed to convert pyruvate to acetyl CoA (important for Krebs cycle)
Term
the role of Niacin (B3) and riboflavin (B2)
Definition
needed to make FAD and NAD (used during Krebs cycle for production of ATP)
Term
the role of Pyridoxine (B6)
Definition
needed for amino acid metabolism
Term
the role of Vitamin C
Definition
antioxidant, helps reduce CV disorders
Term
some fat-soluble vitamins
Definition
-Vitamin A
-vitamin D
-vitamin E
-vitamin K
Term
role of fat-soluble vitamins
Definition
specialized effects
Term
the role of vitamin A
Definition
vision, development
Term
the role of vitamin D
Definition
Ca2+ metabolism
Term
the role of vitamin E
Definition
antioxidant
Term
the role of vitamin K
Definition
blood coagulation/clotting
Term
free radicals
Definition
-Molecules with an unpaired electron in their outer orbital
-Highly reactive, oxidizing or reducing other atoms
Term
some types of free radicals and examples of them
Definition
-Reactive oxygen species (ROS) – O2·- and OH·- -Reactive nitrogen species (RNS) – NO·
Term
some organelles that produce free radicals and why they produce them
Definition
-Mitochondria – oxidative phosphorylation, while producing ATP
-Peroxisomes, NADPH oxidase & other enzymes
Term
some functions of free radicals in the body
Definition
-On WBC – destroy bacteria, cause lymphocyte proliferation
-Wound healing – proliferation of fibroblasts
-Vasodilation by NO·
Term
what happens to cells when there's too many free radicals?
Definition
oxidative stress
Term
the cells that do not get oxidatively stressed by free radicals
Definition
-white blood cells
-fibroblasts in the healing process
Term
how the oxidative stress occurs
Definition
Free radicals – highly toxic to cells (OH·-) --> altering the structures of proteins, nucleic acids, lipids, and other molecules --> cell damage --> cell mutation or death
Term
health effects of oxidative stress
Definition
Promotes aging, inflammatory disease, degenerative diseases & malignant growth
Term
some examples of endogenous antioxidant enzymes
Definition
-Superoxide dismutase & superoxide catalase
-Glutathione peroxidase & glutathione reductase
Term
some examples of exogenous antioxidants
Definition
-beta-Carotene
-vitamin C, E
Term
foods rich in exogenous antioxidants
Definition
Fruits and vegetables
Term
how antioxidants neutralize free radicals
Definition
[image]
Term
depiction of the important balance that occurs between reactive oxygen species (ROS) production and defense
Definition
[image]
Term
some health problems that can result from having not enough free radicals
Definition
-impaired immune function
-impaired cell proliferation
-other impaired responses
Term
Adipose tissue aka...
Definition
-fat cells
-adipocytes
-lipocytes
Term
PPARγ (peroxisome proliferator activated receptors, subtype gamma)
Definition
function as transcription factors for activation of genes for differentiation & metabolism
Term
how the differentiation of preadipocyte occurs
Definition
↑ in circulating fatty acids or prostaglandin (PGJ2) → bind to PPARγ on preadipocytes → ↑ mitosis & differentiation of preadipocytes → ↑ # of adipocytes
Term
PPARγ are in the same family as the...
Definition
R’ for thyroid H, vit A and vit D
Term
Adipostat
Definition
negative feedback loops to defend maintenance of a certain amount of adipose tissue
A hypothesis that keeps the level of body fat within a narrow range despite considerable variations in dietary fat intake and physical activity
Makes it difficult to lose weight
Term
how adipose tissue is an energy source
Definition
-Energy substrate is stored in adipose cells as triacylglycerol (triglycerides, neutral fat)
-The storage and release of neutral fat from adipose cells are hormonally controlled
+Examples – insulin, GH, thyroid H’, adrenal gland H’
Term
how adipose is a hormonal tissue
Definition
-Adipocytes secrete regulatory hormones called adipokines when their PPAR are activated
-Adipokines regulate hunger, metabolism, and insulin sensitivity
-Adipokines include leptin, adiponectin, TNFa, resistin and retinol binding protein-4 (retinol BP4)
Term
adipokines
Definition
Hormones (including leptin, adiponectin, TNFα, resistin and retinol binding protein-4 (retinol BP4)) secreted by adipose cells to regulate hunger, metabolism, and insulin sensitivity
Term
how the leptin secreted by adipose tissue affects some of the organs in the body
Definition
[image]
Term
how the leptin secreted by adipose tissue functions in energy metabolism
Definition
↑ fat tissue → ↑ leptin secretion → ↓ appetite
Term
how the leptin secreted by adipose tissue functions in starvation
Definition
↓ adipose levels --> ↓ leptin levels --> ↓ immune activities
Term
how the leptin secreted by adipose tissue functions in reproduction
Definition
-Leptin levels link whether adequate energy reserves are present for normal reproductive function
-Leptin and timing of puberty
-Amenorrhea (cessation of menstrual cycle) of underweight women
Term
how obesity leads to type 2 diabetes mellitus (DM)
Definition
Obesity → ↑ secretion of leptin, TNFα, resistin and retinol BP4 from adipocytes → … → ↓ insulin secretion → … → type 2 diabetes mellitus (DM)

obesity → ↓ adiponectin secretion → ↓ muscle insulin sensitivity → … → type 2 DM
Term
Adiponectin
Definition
insulin-sensitizing, antidiabetic
Term
depiction of how leptin is involved in the development of type 2 diabetes mellitus (DM)
Definition
[image]
Term
depiction of how adiponectin is involved in the development of type 2 diabetes mellitus (DM)
Definition
[image]
Term
how obesity leads to the cells becoming less sensitive to insulin on the way to developing type 2 diabetes mellitus (DM)
Definition
obesity → ↓ adiponectin secretion → ↓ muscle insulin sensitivity → … → type 2 diabetes mellitus (DM)
Term
how the adipocytes behave differently in child and adult obesity
Definition
-Childhood obesity involves increases in both size & number of adipocytes
-Weight gain in adulthood is due mainly to increase in adipocyte size
Term
how obesity is often diagnosed
Definition
BMI
Term
how to calculate BMI
Definition
BMI = w/h2 w = weight in kilograms h = height in meters
Term
healthy, overweight, and obese BMI ranges
Definition
-Healthy weight is BMI between 19 – 25
-Overweight – >25 BMI
-obesity – > 30 BMI
Term
the importance of BMI
Definition
BMI has a very positive correlation with cardiovascular disorders; higher BMI positively corresponds to higher risk of cardiovascular disorders
Term
the thing in the brain responsible for hunger and regulating eating behavior
Definition
arcuate nucleus of the hypothalamus
Term
how eating is promoted
Definition
Secretion of neuropeptide Y (NPY) & agouti-related protein (AgRP) --> ↑ hunger --> promote eating
Term
how hunger is reduced
Definition
Secretion of melanocyte stimulating hormone (MSH) --> ↓ hunger
Term
how appetite is reduced
Definition
↑ Circulating energy substrates --> ↑ in MSH and ↓ in NPY & ↓ in AgRP secretions --> ↓ appetite
Term
neurotransmitters than can increase overeating
Definition
-Endorphin
-norepinephrine
Term
neurotransmitters than can decrease overeating
Definition
serotonin
Term
depiction of the pathways involving leptin and the hypothalamus that suppress appetite and increase metabolic rate
Definition
[image]
Term
endorphin
Definition
endogenous morphine
Term
analgesic effect
Definition
pain-killing effects of endorphin
Term
peripheral control
Definition
control outside the blood-brain barrier
Term
hormone released by the stomach and what it does
Definition
Ghrelin (stomach) stimulates hunger via arcuate nucleus
Term
hormones released by the small intestine and what they do
Definition
-CCK (SI) promotes satiety
-PYY (SI) responds to caloric content --> ↓ appetite for 12 hrs
Term
Leptin
Definition
a satiety factor, involved in long-term regulation
Term
how leptin is a satiety factor
Definition
-Leptin --> ↓ NPY & ↓ AgRP secretions in arcuate N. --> ↓ hunger
-Leptin --> ↑ MSH --> ↓ hunger
Term
the pathway by which insulin plays a role in satiety
Definition
Insulin --> ↓ NPY --> ↓ hunger
Term
depiction of how the brain, adipose tissue, pancreas, stomach, and small intestine interact with each other to regulate hunger and appetite
Definition
[image]
Term
some functions of CCK
Definition
-contraction of gallbladder, secretion of bile, and then bile acid and bile salt within the bile that can help digestion of fat
-increase and stimulate the secretion of pancreatic digestive enzymes
-promotes satiety, which means the appetite has been reached
-stimulates insulin secretion, increasing the uptake of fatty acids, amino acids, and glucose into the cell
Term
the 2 complementary components of metabolism
Definition
-Anabolism (synthesis)
-Catabolism (hydrolysis)
[image]
Term
Metabolic rate
Definition
-Is total rate of body metabolism -over time, this is equal to the amount of O2 consumed by body/min (over time because anaerobic metabolism is sometimes used)
Term
Basal metabolic rate (BMR)
Definition
-Awake, relaxed, 12-14 hr after eating, at comfortable temp
-affected by age (higher in younger people), sex (tends to be higher in males), body surface area (higher in those with larger surface area), thyroid H'
Term
relationship between thyroid and Basal metabolic rate (BMR)
Definition
-Hyperthyroidism – high BMR
-Hypothyroidism – low BMR
Term
Living cells are maintained by...
Definition
constant expenditure of energy (ATP)
Term
ATP is generated by...
Definition
glycolysis & Krebs cycle
[image]
Term
Fuels used to generate energy include...
Definition
glucose, fatty acids, amino acids, ketone bodies etc.
Term
Calorie
Definition
heat required to elevate 1 cm3 H2O from 14.5-15.5°C
Term
energy content of carbohydrates, proteins, and lipids
Definition
-Carbohydrates & proteins – 4 Kcal/gm
-lipids – 9 Kcal/gm
Term
Normally brain neurons use ______ as the preferred energy sources (E° substrates)
Definition
glucose
Term
When encountering long-term starvation brain neurons can use ______ for energy
Definition
ketone bodies
Term
The preferred energy sources for resting skeletal muscles
Definition
fatty acids
Term
During exercise muscles use...
Definition
glucose
Term
Which cells can only use glucose as the absolute energy sources?
Definition
RBCs, erythrocytes
Term
Why do skeletal muscles prefer to use lipids when at rest and switch to glucose during exercise?
Definition
because at rest, they spare the glucose for use by the brain
Term
why red blood cells can only use glucose for energy
Definition
because they don't have mitochondria, and therefore no Krebs cycle
-they can only do glycolysis
Term
Absorptive state
Definition
-within 4 hr period after eating
-Absorption of abundant energy substrates (anabolic)
Term
some anabolic processes that occur during the absorptive state
Definition
-Glucose in excess → ↑ glycogenesis in liver (main) & skeletal muscles
+If excess exists after full glycogenesis → ↑ lipogenesis
-Fatty acids in excess → ↑ lipogenesis
-Amino acids in excess → ↑ protein synthesis
Term
why too much sugar results in obesity
Definition
because if excess exists after full glycogenesis → ↑ lipogenesis
Term
Postabsorptive state
Definition
–fasting state, > 4 hr after the meal
-Use of the stored energy substrates for energy (catabolic)
Term
some catabolic processes that occur during the postabsorptive state
Definition
↑ Glycogenolysis, lipolysis & protein degradation
Term
some energy-producing processes that occur during short-term to long-term starvation states
Definition
-gluconeogenesis
-ketogenesis
Term
Gluconeogenesis
Definition
formation of glucose from non-carbohydrates (amino acids, glycerol, lactate etc.)
Term
Ketogenesis
Definition
formation of ketone bodies from lipids
Term
Glycolysis
Definition
Conversion of glucose into two molecules of pyruvic acid
Term
Glycogenesis
Definition
The production of glycogen, mostly in skeletal muscles and the liver
Term
Glycogenolysis
Definition
Hydrolysis (breakdown) of glycogen; yields glucose 6-phosphate for glycolysis, or (in the liver only) free glucose that can be secreted into the blood
Term
Gluconeogenesis
Definition
The production of glucose from noncarbohydrate molecules, including lactic acid and amino acids, primarily in the liver
Term
Lipogenesis
Definition
The formation of triglycerides (fat), primarily in adipose tissue
Term
Lipolysis
Definition
Hydrolysis (breakdown) of triglycerides, primarily in adipose tissue
Term
Ketogenesis
Definition
The formation of ketone bodies, which are four-carbon-long organic acids, from fatty acids; occurs in the liver
Term
specific disease in which the patient often has ketogenesis
Definition
diabetes mellitus
Term
The body's transiion between anabolism and catabolism is mainly regulated by...
Definition
hormones
Term
some hormone changes in absorptive and postabsorptive states
Definition
-Absorptive state – ↑ insulin secretion
-postabsorptive state – ↑ glucagon secretion
Term
diagram showing how the balance between anabolism and catabolism is maintained
Definition
[image]
Term
some hormones involved in maintaining the balance between anabolism and catabolism
Definition
antagonistic effects of insulin, glucagon, GH, T3, cortisol, and Epi
Term
some hormones that regulate metabolism under certain physiological conditions
Definition
-Adrenal hormones (H) – stress
-Thyroid H – basal metabolic rate & growth
-GH – growth & maintenance
Term
why insulin secretion increases in the absorptive state
Definition
overabundant of E° substrates (glucose, amino acids & fatty acids) --> ↑ insulin secretion
-Overall strategy – ↓ blood levels of E° substrates by storing in tissues
Term
some things that are caused by increased insulin levels
Definition
When blood [insulin] increases --> ↑ anabolism and ↓ catabolism
-↑ Insertion of glucose transporters 4 on skeletal, cardiac muscles & fat tissue
+↑ Cellular uptake of glucose
-↑ Glycogenesis – ↑ entry of glucose into liver & skeletal muscle cells --> ↑ glycogen storage
-↑ Lipogenesis – ↑ neutral fat in adipose cells
-↑ Cellular uptake of amino acids --> ↑ proteins synthesis
Term
how insulin and glucagon interact with liver cells
Definition
[image]
Term
how insulin interacts with adipose cells
Definition
[image]
Term
why glucagon levels increase in the postabsorptive state
Definition
Postabsorptive state --> ↓ blood levels of glucose & fatty acids
-Overall strategy – to maintain blood glucose & fatty acids
Term
depiction of what happens how the adipose, liver, and skeletal muscles interact with each other during fasting
Definition
[image]
Term
some things that happen when glucagon levels increase
Definition
-↑ glucagon --> ↑ Glycogenolysis in the liver --> ↑ blood glucose levels
-Also, ↑ glucagon --> ↑ lipolysis --> ↑ blood fatty acid levels (skeletal muscle, heart, liver, & kidneys use fatty acids as major source of fuel)
Term
what higher glucagon levels lead to during mid- to long-term starvation
Definition
↑ Gluconeogenesis & ketogenesis
Term
Normal fasting [glucose] levels
Definition
65 - 100 mg/dl
Term
how blood glucose levels are maintained during the absorptive state
Definition
Absorptive state – ↑ blood [glucose] (main effect) or ↑ blood [amino acids] --> ↑ insulin secretion
-↑ Blood [glucose] --> glucose binds to glucose transporter GLUT2 in β cells (GLUT2 is not insulin-regulated) --> ↑ insulin secretion --> glucose enters cells
-Insulin and glucagon normally prevent levels from rising above 170 mg/dl or falling below 50 mg/dl
Term
how blood glucose levels are maintained during the postabsorptive state
Definition
Post-absorptive or stressful state – ↑ glucagon
-↑ Glucagon secretion occurs only when ↓ blood [glucose]
Term
meals that increase levels of both insulin and glucagon anh why they do it
Definition
meals high in protein and low in carbohydrates
-this is because amino acids stimulate insulin production and low carbs stimulate glucagon production
-a perfect example of this is the Atkins diet
Term
why hypoglycemia can cause neurological problems
Definition
because neurons rely mainly on glucose
Term
the effect of the autonomic nervous system on blood glucose levels
Definition
-Sympathetic effect - “fight or flight”, enhances glucagon secretion, stress hyperglycemia
-Parasympathetic effect - “rest and repair”, “+” insulin
Term
the 3 hormones that regulate insulin and glucagon secretion and how they do it
Definition
-GIP
-CCK
-GLP-1
-Glucose in gut --> ↑ GIP (glucose-dep. insulinotropic peptide) secretion --> ↑ insulin secretion, ↓ gastric motility
+Glucose ingestion vs. i.v. glucose injection
-CCK (cholecystokinin) --> ↑ insulin secretion, ↑ secretion of bile and pancreatic digestive enzymes
-↑ Blood glucose, amino acids, fatty acids --> ↑ GLP-1 (glucagon-like peptide, incretin) --> ↑↑↑ insulin, β cell proliferation & ↓ appetite (potent anti-hyperglycemic)
Term
how higher glucagon levels lead to stimulation of sympathetic division of the ANS
Definition
higher glucagon --> glycogen breakdown --> higher blood glucose levels stimulation of sympathetic division of ANS for "fight-or-flight" reaction
Term
why ingesting sugar causes more insulin release than injecting sugar
Definition
because ingesting it, there's contact with the epithelial cells of the small intestine, leading to more secretion of insulin
Glucose in gut --> ↑ GIP (glucose-dep. insulinotropic peptide, or gastric inhibitory peptide) secretion --> ↑ insulin secretion, ↓ gastric motility
Term
glucagon-like protein 1 (GLP-1)
Definition
-stimulates insulin secretion and decreases glucagon secretion
-this is a potent anti-hyperglycemic hormone

-↑ Blood glucose, amino acids, fatty acids --> ↑ GLP-1 (glucagon-like peptide, incretin) --> ↑↑↑ insulin, β cell proliferation & ↓ appetite (potent anti-hyperglycemic)
Term
Diabetes mellitus (DM)
Definition
chronic ↑ in blood [glucose]
Term
Type 1 Diabetes mellitus (DM)
Definition
juvenile-onset, insulin-dependent (ID) DM
-Occurs mainly at juvenile age, ~5% of DM patients
Term
how Type 1 Diabetes mellitus (DM) is an autoimmune disease
Definition
-the virus that causes it resembles glutamate dacarboxylase
-as a result, killer T cells target glutamate decarboxylase in Beta cells → Beta cells destroyed, Alpha cells active → ↓ insulin
Term
in type 1 diabetes, hyperglycemia is due to...
Definition
-Lack of insulin → glucose cannot enter the adipose cells
-↑ Glucagon/insulin ratio → ↑ glycogenolysis in liver → ↑ glucose exit into blood from liver → hyperglycemia
-Lack of insulin → rate of lipolysis > rate of lipogenesis → ↑ fatty acids in blood
-Fatty acids converted to ketone bodies → hyperketonemia → ketoacidosis → coma
Term
why someone with type 1 diabetes may need to drink lots of water
Definition
because type 1 diabetes causes Osmotic diuresis
-Osmotic diuresis → glucosuria, dehydration
Term
Osmotic diuresis
Definition
increase in blood volume caused by osmotic pressure
-often seen in type 1 diabetes
Term
why people with type 1 diabetes may have larger appetites
Definition
because glucose and fatty acids can't enter the cells, due to lack of insulin
Term
some details about Type 2 Diabetes Mellitus (DM)
Definition
-aka non-insulin-dependent (NIDDM)
-Account for 95% of DM patients
-Insulin resistance – cells fail to respond to insulin actions
-Blood [insulin] may be high or normal until late stage
-Slow to develop, genetic factors play a role
-Occurs mostly in mid-age people who are overweight
Term
how insulin resistance leads to type 2 diabetes
Definition
When fat and muscle cells fail to respond adequately to circulating insulin, blood glucose levels rise
-glucose and fatty acids can't enter cells, due to insulin resistance
Term
treatment for type 2 diabetes
Definition
Treatment – change in lifestyle:
-Increase exercise → ↑ GLUT-4 in the skeletal muscle cells (makes them more responsive to insulin)
-Weight reduction – ↑ fiber in diet, ↓ saturated fat
Term
the primary cause of type 2 diabetes
Definition
insulin resistance
Term
hypothesis for how increased dietary levels of polyunsaturated fatty acids can treat type 2 diabetes
Definition
↑ polyunsaturated fatty acids → ↑ cell membrane fluidity → ↑ insulin R’ # → ↑ affinity of insulin to its receptors → ↓ insulin resistance
Term
oral glucose tolerance test
Definition
one way to tell whether or not a patient has diabetes
-A person drinks a glucose solution and blood samples are taken periodically
-Normal person’s rise in blood [glucose] after drinking solution is reversed to normal in 2 hrs
-measures...
+Ability of Beta cells to secrete insulin (insulin secretion)
+Ability of insulin to lower blood glucose (insulin-resistance)
[image]
Term
indicator of diabetes after the oral glucose tolerance test
Definition
Blood [glucose] levels in DM patients remain > 200 mg/dl 2 hr following glucose ingestion
[image]
Term
Reactive hypoglycemia
Definition
-Symptoms of hypoglycemia
-Insulin injections → insulin shock
[image]
Term
the oral glucose tolerance test measures...
Definition
-Ability of Beta cells to secrete insulin (insulin secretion)
-Ability of insulin to lower blood glucose (insulin-resistance)
[image]
Term
adrenal medulla secretes...
Definition
-epinephrine (E)
-norepinephrine (NE)
Term
effects of the epinephrine (E) and norepinephrine (NE) secreted by the adrenal medulla
Definition
-Fight or flight (sympathetic, short-term stress) --> need glucose for CNS & skeletal muscles
-epinephrine ↑ Glycogenolysis --> hyperglycemia
-epinephrine ↑ Lipolysis, converting fat into fatty acids – glucagon-like effects
-Second messenger – cAMP (similar to glucagon)
Term
adrenal cortex secretes...
Definition
glucocorticoids (e.g. cortisol)
Term
effects of the glucocorticoids (e.g. cortisol) secreted by the adrenal cortex
Definition
-Long-term stress --> ↑ hypothalamic CRH --> ↑ pituitary ACTH --> ↑ glucocorticoids secretion
-↑ Glucagon secretion --> glycogenolysis --> hyperglycemia
-↑ Lipolysis, ketogenesis & hyperketoemia
-↑ Protein breakdown, gluconeogenesis --> hyperglycemia & general weakness
Term
what the word glucocorticoid means
Definition
steroid hormone secreted by the adrenal cortex for glucose metabolism
-gluco: glucose
-corti: adrenal cortex
-coid: steroid
Term
the stress associated with glucocorticoids
Definition
long-term stress
Term
Hyperketonemia
Definition
too much ketone bodies in the blood
Term
the 2 thyroid hormones released by the thyroid gland
Definition
Main form is T4 (thyroxine), active form is T3
Term
some effects of thyroid hormone
Definition
-Basal metabolic rate (BMR)
-Calorigenic effects (↑ metabolic heat) and cold adaptation
Term
Calorigenic effects
Definition
↑ metabolic heat
Term
role of T4 in growth and development
Definition
-Protein synthesis
-Growth of skeleton
-Contributes to proper growth and development of CNS – prenatal to 6 months after birth
Term
symptoms of Hyperthyroidism
Definition
high BMR, weight loss, nervousness, irritability, intolerance to heat
Term
symptoms of Hypothyroidism
Definition
cretinism, myxedema, lethargy, weight gain, increased sleep, lower b.t., coarse skin, slow pulse and reflex, depression
Term
Cretinism
Definition
mental retardation during fetal or neonatal stage caused by hypothyroidism
Term
myxedema
Definition
when hypothyroidism causes edema by attracting mucoproteins into the extracellular fluid from the blood plasma into interstitial fluid
Term
diagram of what growth hormone influences and what that leads to
Definition
[image]
Term
secretion of growth hormone (GH) controlled by...
Definition
growth hormone inhibiting hormone (GHIH) and growth hormone releasing hormone (GHRH), both released by the hypothalamus
Term
growth hormone inhibiting hormone (GHIH) and growth hormone releasing hormone (GHRH) are released by the...
Definition
hypothalamus
Term
growth hormone released by the...
Definition
anterior pituitary
Term
indirect effects of growth hormone (somatotropin)
Definition
(↑ body growth) – effects on bone & muscles, mediated by IGF 1
[image]
Term
direct effects of growth hormone (somatotropin)
Definition
-Anabolic effects – ↑ protein synthesis, ↑ cell uptake of amino acids
-Catabolic effects – ↑ lipolysis, ↑ blood [fatty acids], ↑ use of fatty acids
[image]
Term
Diabetogenic effect of growth hormone (somatotropin)
Definition
↓ glycolysis rate, ↓ glucose utilization --> hyperglycemia
[image]
Term
what the word somatotropin means
Definition
A substance stimulates the growth of body
-"In" is a substance
-"Trop" is the growth of
-"Somato" means body
Term
indirect effect of growth hormone (somatotropin) mediated by...
Definition
IGF-1 from the liver
Term
In childhood, GH overproduction leads to...
Definition
gigantism
Term
In childhood, GH underproduction leads to...
Definition
dwarfism
Term
In adulthood, GH overproduction leads to...
Definition
acromegaly (jaw elongation; deformities in face, hands & feet bones)
Term
Importance of plasma Ca2+ in the body
Definition
Bone structure, muscle contraction, neurotransmission, second messenger, membrane permeability, maintaining membrane potential
Term
hypocalcemia leads to...
Definition
enhanced nerve excitability --> muscle spasm (tetanus)
Term
some sources of of plasma Ca2+
Definition
-Bone deposition and resorption +Skeleton also serves as a storage of Ca2+ +Osteoblasts for bone deposition (collagen + Ca2+) vs. osteoclasts for bone resorption -Intestinal absorption and urinary excretion
Term
depiction of how the osteoclast degrades bone
Definition
[image]
Term
hypocalcemia
Definition
low blood calcium
Term
osteoblast
Definition
-for bone deposition
-It will deposit collagen, and collagen is a network or meshwork, and then calcium and phosphate will deposit to form the bone structure
Term
osteoclast
Definition
-for bone resorption
-takes calcium away from the bone
Term
Parathyroid hormone (PTH)
Definition
-polypeptide hormone secreted from parathyroid gland -increases blood Ca2+ -Single most important hormone in the control of blood [Ca2+] -Stimulating bone resorption of Ca2+ -Stimulating renal reabsorption of Ca2+ -Inhibiting renal reabsorption of PO43- -Promoting formation of (OH)2 Vit D3
Term
Over-secretion of PTH leads to...
Definition
osteoporosis
Term
depiction of where the parathyroid glands are
Definition
[image]
Term
parathyroid glands
Definition
-attached to, but not part of, thyroid gland
-secretes parathyroid hormone, which is a polypeptide hormone
Term
how parathyroid hormone (PTH) increases blood Ca2+
Definition
-Stimulating bone resorption of Ca2+ -Stimulating renal reabsorption of Ca2+ -Inhibiting renal reabsorption of PO43- -Promoting formation of dihydroxyl ((OH)2) Vit D3
Term
precursor to vitamin D3
Definition
7-dehydrocholesterol
Term
the bioactive form of vitamin D3
Definition
1,25-dihydroxy-vitamin D3
Term
the organs that form 1,25-dihydroxy-vitamin D3
Definition
liver and kidneys
Term
how 1,25-dihydroxy-vitamin D3 helps regulate Ca2+ absorption
Definition
stimulates... -Intestinal absorption of Ca2+ -Bone resorption of Ca2+ -Renal re-absorption of Ca2+
Term
depiction of the sunlight-dependent pathway that forms 1,25-dihydroxy-vitamin D3
Definition
[image]
Term
the negative feedback loop 1,25-dihydroxy-vitamin D3 is involved in
Definition
[image]
Term
Calcitonin
Definition
-a peptide hormone secreted by parafollicular (C) cells in the thyroid gland (not parathyroid) -lowers plasma Ca2+ by ↓ bone resorption (↓ osteoclasts activity) and ↓ renal reabsorption (↑ urinary excretion of Ca2+)
Term
how calcitonin lowers plasma Ca2+
Definition
-↓ Bone resorption – ↓ osteoclast activity
-↓ Renal re-absorption – ↑ urinary excretion of Ca++
Term
the negative feedback loop calcitonin is in
Definition
[image]
Term
parafollicular cells
Definition
small cells in the thyroid gland that secrete calcitonin and are just outside the follicles
[image]
Term
a treatment for osteoporosis that uses calcitonin
Definition
nasal spray that gets absorbed through the mucosal layer of the respiratory tract
Term
how the thyroid responds to high Ca levels
Definition
by secreting calcitonin
Term
how estrogen regulates bone growth
Definition
-Causes sealing (ossifying) of epiphyseal disc (cartilaginous growth plates) --> stops growth
-Is necessary for proper bone mineralization & prevention of osteoporosis
-Stimulates osteoblast activity & suppresses formation of osteoclasts
[image]
Supporting users have an ad free experience!