lecture 5 - the endocrine system and its response to exercise

Question 1

what are the major endocrine glands

Answer 1

pituitary, thyroid, parathyroid, adrenal, pineal, thymus, pancreas, gonads, hypothalamus and adipose tissues

Question 2

what does the endocrine system consist of

Answer 2

host organ, chemical messenger and target organ

Question 3

what are chemicals

Answer 3

chemical substances synthesized by specific host glands

Question 4

What are the types of hormones

Answer 4

steroid hormones and amine/ polypeptide hormones

Question 5

How does hormones alter cellular reactions of a specific target cell

Answer 5

1. modifying rate of intracellular protein synthesis
2. changing rate of enzyme activity
3. altering plasma membrane transport
4. inducing secretory activity

Question 6

what influences a target cell’s activation by hormones

Answer 6

1. hormone concentration in blood
2. number of target cell receptors for the hormone
3. sensitivity or strength of the union between the hormone and its receptor

Question 7

what is cyclic AMP

Answer 7

a secondary messenger to activate a specific protein kinase

Question 8

describe the factors that establish the sequence of reactions by cyclic AMP

Answer 8

1. type or target cell
2. specific enzymes contained in target cell
3. specific hormones that act as first messenger

Question 9

how do hormones increase enzyme activity

Answer 9

1. stimulating enzyme production
2. combining with enzyme to alter its shape and ability to act
3. activating inactive enzyme forms

Question 10

describe the factors that determine the plasma concentration of hormones

Answer 10

1. quantity synthesised in host gland
2. rate of either catabolised or secretion into blood
3. Quantity of transport proteins preset
4. changes in plasma volume

Question 11

describe the hormonal factors that stimulate endocrine gland activity

Answer 11

hormones increase the secretion of another hormone

Question 12

describe the humeral factors that stimulate endocrine gland activity

Answer 12

changes levels of ions and molecules to initiate / inhibit hormones

Question 13

describe the neural factors that stimulate endocrine gland activity

Answer 13

nerve stimulates the release of hormones

Question 14

how does GH facilitate protein synthesis

Answer 14

1. increase amino acid transport through the plasma membrane
2. stimulating RNA formation
3. activating cellular ribosomes that increase protein synthesis

Question 15

describe the functions of growth hormone

Answer 15

1. promote cell division and cellular proliferation throughout the body
2. slows down carbohydrate breakdown and initiates mobilisation and use fat for energy

Question 16

How does physical activity augments growth hormones action on target cells

Answer 16

1. benefits muscle, bind and connective tissue growth and remodelling
2. optimised fuel mixture during physical activity
3. net metabolic effect preserves plasma glucose concentrations for CNS and muscle functions

Question 17

describe the factors that influence IGF transport

Answer 17

1. binding proteins within muscle
2. nutritional status
3. plasma insulin levels

Question 18

what are the functions of Thyrotropin

Answer 18

1. control thyroid gland secretion
2. maintains growth and development of thyroid gland and increases thyroid cell metabolism

Question 19

What are the functions of ACTH

Answer 19

1. enhance FFA mobilisation from adipose tissue
2. increases gluconeogenesis
3. stimulate protein catabolism

Question 20

state the functions of Gonadotropic Hormones

Answer 20

stimulate male and female sex organs to grow and secrete hormones at a faster rate

Question 21

state the functions of follicle stimulating hormone

Answer 21

1. initiates follicle growth in ovaries and stimulates estrogen secretion
2. in males, promotes sperm development

Question 22

state the functions of Luitenizing Hormone

Answer 22

1. cause estrogen secretion and follicle rupture
2. stimulates testes to secrete testosterone

Question 23

state the function of ADH

Answer 23

inhibit water excretion by the kidneys

Question 24

state the function of Thyroxine (T4)

Answer 24

raise metabolism except in brain, spleen, testes, uterus, and thyroid gland

Question 25

state the function of Triiodothronine (T3)

Answer 25

facilitates neural reflex activity

Question 26

describe hyperthyroidism effects on an individuals quality of life

Answer 26

1. increase VO2 and metabolic heat production during rest 2. increased protein catabolism and subsequent muscle weakness and weight loss 3. heightened reflex activity and physiological disturbances ranging from irritability and insomnia to psychosis 4. rapid heart rate

Question 27

describe hypothyroidism effects on the quality of life

Answer 27

1. reduced metabolic rate and cold-intolerance from reduced internal heat production 2. decreased protein synthesis produces brittle nails, thinning hair and dry, thin skin 3. depressed reflex activity, slowed speech and though processing and feelings of fatigue 4. slow heart rate

Question 28

describe the effects of parathyroid hormones

Answer 28

1. activation of osteoclasts digests bone matrix to release ionic calcium and phosphate to blood 2. enhancement of calcium ion reabsorption and decreased kidney retention of phosphate 3. increased calcium absorption by intestinal mucosa

Question 29

what hormones are secreted ny the adrenal medulla

Answer 29

epinepherine and norepinepherine

Question 30

state the function of epinepherine

Answer 30

stimulate glycogenolysis

Question 31

state the function of norepineherine

Answer 31

provides powerful lipolytic stimulation in adipose tissue

Question 32

state the function of the adrenal cortex

Answer 32

secrete adrenocortical hormones

Question 33

what is the function of mineralocorticoids

Answer 33

regulates mineral balance in extracellular fluid

Question 34

what is the main mineralocorticoids

Answer 34

aldosterone

Question 35

state the function of aldosterone

Answer 35

1. control sodium concentration and extracellular fluid volume 2. stimulates sodium ion reabsorption in distal kidney tubules 3. helps stabilize serum potassium and pH 4. major effects during recovery from physical activity

Question 36

what is the main glucocorticoid

Answer 36

cortisol

Question 37

state the main functions of cortisol

Answer 37

1. promote breakdown of protein to amino acids 2. supports actions of other hormones 3. serves as an insulin antagonist by inhibiting cellular glucose uptake and oxidation 4. promotes triacylglycerol breakdown to glycerol and FA in adipose tissue 5. suppress immune system function 6. produces negative calcium balance

Question 38

state the function of testosterone

Answer 38

initiate sperm production and stimulates development of male secondary sex characteristics

Question 39

state the function of estrogen

Answer 39

regulate ovulation, menstruation and physiologic adjustment during pregnancy

Question 40

state the function of progesterone

Answer 40

contribute regulatory input to female reproductive cycle, uterine smooth muscle action and lactation

Question 41

state the function of glucagon

Answer 41

primarily stimulates both glycogenolysis and gluconeogenesis by liver and increase lipid catabolism

Question 42

state the functions of insulin

Answer 42

1. regulates glucose entry into all tissues except the brain 2. trigger intracellular enzyme activity that facilitates protein synthesis

Question 43

how does insulin stimulate an enzymes activity to faciliate protein synthesis

Answer 43

1. increase amino acid transport 2. increase cellular RNA levels increases protein formation by ribosomes

Question 44

what are the main glucose transporters in the muscles

Answer 44

GLUT-1 and GLUT-4

Question 45

why do endurance trained individuals show less rise in blood GH levels

Answer 45

reduced exercise stress as training professes and fitness improves

Question 46

why does training increase ACTH release during physical activity

Answer 46

stimulation of adrenal gland activity to promote fat catabolism and spare glycogen

Question 47

what 3 factors require a greater SNS activation from catecholamine output

Answer 47

1. greater absolute demand for substrate use via glycogenolysis and lipolysis 2. increased cardiovascular response 3. larger muscle mass activation

Question 48

describe the short term exercise effects on immune function (moderate exercise)

Answer 48

boosts natural immune functions and hosts defences for up to several hours

Question 49

describe the short term exercise effects on immune function (exhaustive exercise)

Answer 49

severely depresses body's first line of defence against infection

Question 50

describe the long term exercise effects on immune function

Answer 50

positively affects natural immune functions in young and old and obese during weight loss