Exam 2 Review Slides

Question 1

upregulation

Answer 1

increase in receptor number in response to low concentration of hormone increases sensitivity
ex) stress hormone concentration was low after a period of no exercise many receptors are causing very high BP and HR in response to exercise

Question 2

downregulation

Answer 2

decrease in receptor number in response to high concentration of hormone
ex) high cortisol in bloodstream leads to a decrease in cortisol receptors to prevent cortisol from attacking proteins and breaking down tissue

Question 3

the magnitude of hormone effect is dependent on (3)

Answer 3

1. concentration of hormone (blood volume)
2. number of receptors on cell
3. affinity of the receptor for the hormone

Question 4

Endocrine glands

Answer 4

• release hormones directly into bloodstream
• ductless

Question 5

Hormones & their divisions

Answer 5

• bind to protein receptors to exert specific effect
• divided into: amino acid derivatives, peptides, steroids

Question 6

mechanisms of hormone action: activation of genes genes to alter protein synthesis levels

Answer 6

steroid hormones

Question 7

mechanisms of hormone action: second messengers in the cell via G protein

Answer 7

cyclin AMP (cAMP)
CA++
Inositol triphosphate
Diacylglycerol (DAG)

Question 8

Hypothalamus

Answer 8

• most initial signals for hormone secretion comes from here
• stimulates release of hormones from anterior pituitary gland by releasing hormones or factors
• provides hormones for release from posterior pituitary gland

Question 9

Anterior pituitary gland (7)

Answer 9

-most hormones from here are stimulating/releasing, their job is to move down and affect other glands that produce hormones with biological effect
- adrenocortizotropic hormone (ACTH)
- follicle-stimulating hormone (FSH)
- Lutenizing hormone (LH)
- Melanocyte-stimulating hormone (MSH)
- Thyroid-stimulating hormone (TSH)
- Prolactin
- Growth hormone (GH)

Question 10

Posterior pituitary gland

Answer 10

• oxytocin
• antidiuretic hormone (ADH),, acts on kidneys to reduce water loss to maintain plasma volume

Question 11

Thyroid gland

Answer 11

• stimulated by TSH
• releases calcitonin, regulates plasma Ca++ BLOCKS release from bone when Ca++ concentration is high

Question 12

Parathyroid gland

Answer 12

• parathyroid hormone, primary regulator of plasma Ca++, STIMULATES Ca++ release from bone when concentration is low, STIMULATES reabsorption of Ca++ by kidneys

Question 13

Adrenal medula

Answer 13

• above (inside) kidney
• secrete catecholamines: epinephrine and norepinephrine

Question 14

Epinephrine and norepinephrine

Answer 14

• fast-acting hormones, part of “fight or flight”
• bind to adrenergic receptors, alpha and beta

Question 15

adrenal cortex

Answer 15

• outside portion of gland above kidney
• secretes steroid hormones, aldosterone, cortisol, sex steroids

Question 16

renin and aldosterone

Answer 16

hormones for blood pressure control, water balance, control of Na+ reabsorption and K+ secretion

Question 17

pancreas

Answer 17

• both exocrine and endocrine functions
• releases insulin, glucagon, somatostatin, and digestive enzymes and bicarbonate

Question 18

glycogenolysis is related to

Answer 18

exercise intensity
high intensity exercise results in greater and more rapid glycogen depletion (around 75% VO2 max)

Question 19

Plasma epinephrine

Answer 19

• stimulates glycogenolysis
• high intensity exercise results in more plasma epinephrine
  faster glycogen depletion in high intensity rages is mediated by epinephrine

Question 20

control of muscle glycogen breakdown

Answer 20

• under dual control
• predominant mechanism: epinephrine-cyclic AMP (second messenger), via beta-androgenic receptors, E binds to B-receptor which uses cyclic-AMP which leads to glycogenolysis
• backup mechanism: Ca++ calmodulin

Question 21

4 processes that maintain plasma glucose

Answer 21

• mobilizing glucose from liver glycogen stores
• mobilizing FFA from adipose tissue to spare blood glucose
• gluconeogenesis from amino acids lactic acid and glycerol
• blocking entry of glucose into cells, forces use of FFA

Question 22

Effectors from control for plasma glucose

Answer 22

• slow acting: thyroxine, cortisol, growth hormone
• fast acting: epinephrine, norepinephrine, insulin and glucagon

Question 23

Insulin vs glucagon roles

Answer 23

• insulin uptake and storage of glucose and FFA, decrease during exercise and following training
• glucagon released by pancreas to mobilized glucose and FFA during exercise, decreased following training

Question 24

2 adjustments of blood flow during exercise

Answer 24

• increased cardiac output
• redistribution of blood flow from inactive organs to active skeletal muscle

Question 25

pulmonary circuit

Answer 25

- right side of heart - pumps deoxygenated blood to lungs via pulmonary arteries - returns oxygenated blood to left side of heart via pulmonary veins

Question 26

systemic circuit

Answer 26

- left side of heart - pumps oxygenated blood to body via arteries - returns deoxygenated blood to the right side of the heart via veins

Question 27

layers of the heart

Answer 27

- epicardium -myocardium (contracts) - endocardium

Question 28

cardiac vs skeletal muscles

Answer 28

Both: striated, contain contractile proteins and actin and myosin - cardiac muscles are shorter and branched - cardiac muscles are connected by incercalated discs - cardiac muscles are aerobic and have many mitochondria gut only one nucleus - skeletal muscle fibers have satellite cells

Question 29

phases of the cardiac cycle, how exercise impacts them

Answer 29

- systole: contraction - diastole: relaxation - during exercise diastole gets significantly shorter

Question 30

Factors that influence arterial blood pressure

Answer 30

- blood volume increase, HR increase, SV, blood viscosity, and peripheral resistance increase all cause an increase in arterial blood pressure

Question 31

mean arterial pressure (MAP), equation, regulation

Answer 31

average pressure in arteries - cardiac output * total vascular resistance MAP=DBP + 0.33(SBP-DBP) - Short term regulation: SNS and baroreceptors (increase in SNS activity = decrease in BP) - long term regualation: kidneys via control of blood volume, reduce blood volume -> decrease SV -> reduce cardiac output-> decrease in MAP (similar to diuretics medication)

Question 32

pacemaker for heart

Answer 32

SA node (sinoatrial node) - in right atria, initiates depolarization

Question 33

AV node (atrioventricular node)

Answer 33

- passes depolarization to ventricles

Question 34

bundle branches

Answer 34

connect atria to left and right ventricle

Question 35

purkinje fivers

Answer 35

spread wave of depolarization throughout the ventricle

Question 36

electrocardiogram (ECG)

Answer 36

records electrical activity of the heart - P wave, atrial depolarization - QRS complex, ventricular depolarization and atrial repolarization - T wave, ventricular repolarization

Question 37

cardiac output (Q)

Answer 37

Q= HR * SV

Question 38

Heart rate regulation

Answer 38

- PNS via vagus nerve, slows HR by inhibiting SA and AV node - SNS via cardiac accelerator nerves, increases HR by stimulating SA and AV node

Question 39

3 effectors of stroke volume

Answer 39

- Average aortic blood pressure, afterload - strength of ventricular contraction, contractility - end-diastolic volume (EDV), preload

Question 40

Average aortic blood pressure, afterload

Answer 40

- pressure the heart must pump against to eject blood (MAP)

Question 41

strength of ventricular contraction, contractility

Answer 41

- enhanced by circulating E and NE and direct sympathetic stimulation of the heart

Question 42

end-diastolic volume (EDV), preload

Answer 42

- volume of blood in ventricles at the end of diastole

Question 43

fick equation

Answer 43

VO2 = Q x a-vO2 difference

Question 44

HRmax=208-(0.7*age)