Topic 7: Animal Control Systems

Question 1

Define Hormones

Answer 1

signalling molecules secreted into the extracellular fluid and circulated in the blood through the body

Question 2

What do hormones do?

Answer 2

Communicate regulatory messages, help with sexual development, and coordinate physiological responses throughout the body

Question 3

How do hormones get a response?

Answer 3

If the specific receptor on the target cell matches the hormone.

Question 4

Endocrine system what is it and what does it do

Answer 4

Chemical signalling within the body via secreted hormones. (long distance) Regulates reproduction, development, metabolism, and behaviour.

Question 5

Nervous system what is it and what does it do

Answer 5

network of neurons that transmits signals along specialized pathways. Regulates neurons, muscle cells and endocrine cells

Question 6

What are the 5 forms of signalling

Answer 6

endocrine, paracrine, autocrine, synaptic and neuroendrocrine.

Question 7

Endocrine signalling

Answer 7

Secreted molecules diffuse into the bloodstream (or hemolymph) and trigger responses in target cells anywhere in the body.

Question 8

Paracrine signalling

Answer 8

secreted molecules diffuse locally and trigger a response in neighbouring cells.

Question 9

Autocrine signalling

Answer 9

secreted molecules diffuse locally and trigger a response in the cell that secreted them, (auto=self).

Question 10

Synaptic signalling

Answer 10

neurotransmitter diffuse across synapses and trigger responses in target tissues (neurons, muscles, glands).

Question 11

Neuroendrocrine signalling

Answer 11

Neurohormones diffuse into the bloodstream and trigger responses anywhere in the body.

Question 12

Neurohormones

Answer 12

Hormones secreted by neurosecretory cells (ex: antidiuretic hormone in the kidneys)

Question 13

what are pheromones, and what are their purposes?

Answer 13

chemicals secreted into the external environment. For defining territories, warning predators and attracting mates.

Question 14

Gaseous signaling factors

Answer 14

small and neutral charged, easily diffuses. Cannot travel far, so act locally.

Question 15

Many hormones are

Answer 15

proteins ex: insulin is an inactive polypeptide activated when blood glucose levels are too high.

Question 16

amine hormones are produced from

Answer 16

amino acids

Question 17

are proteins hydrophilic or hydrophobic

Answer 17

hydrophilic

Question 18

are amine hormones hydrophilic or hydrophobic or both?

Answer 18

both

Question 19

lipid signalling factors

Answer 19

Mostly fatty acids and steroids, have very specific structures

Question 20

are lipid signalling factors hydrophobic or hydrophillic

Answer 20

Hydrophobic

Question 21

prostaglandins

Answer 21

modified fatty acids produced in many cell types

Question 22

Steroids

Answer 22

sex hormones and cholesterol

Question 23

what are the differences between (hydrophilic) and lipid soluble (hydrophobic)

Answer 23

Water soluble hormones require a vesicle in the secretory cell (or they would dissolve), so they require exocytosis. They dissolve in the blood. They need a receptor protein to get into the target cell because they’re polar. And there is a signal transduction pathway. Lipid soluble hormones diffuse directly from that secretory cell without a vesicle, but they have transport proteins in the blood and can diffuse directly into the cell without a receptor protein but they have receptors in the cytosol that move into the nucleus after binding. There is no signal transduction, because the hormone is delivered directly to the target cell and location, so don’t need to be transduced. This still triggers gene expression though.

Question 24

signal transduction

Answer 24

multi-step cascade of events, proteins change form to transmit the cellular signal.

Question 25

explain the signal transduction in a stress response (epinepherine aka adrenaline secreted)

Answer 25

Gets transported to the liver and binds to a G protein - coupled receptor on the membrane of the target cell. Causes a cascade of events. Synthesis of cAMP (secondary messenger). cAMP activates protein kinase that activates enzyme that breaks down glycogen (for fast energy to run away).

Question 26

Thyroid hormone receptors what happens in absence vs presence of protein

Answer 26

attach to genes in the absence of the hormones, repressing transcription. When hormone (thyroxine) is present it enters the cell and binds to the receptor, causing the receptor to release the DNA element and allow transcription.

Question 27

Thyroid hormones where produced, target tissue, function

Answer 27

Produced in the thyroid gland, target tissue throughout body, stimulates and maintains metabolic processes.

Question 28

calcitonin where produced, target tissue, function

Answer 28

In the thyroid gland, target tissue: bones and kidneys, lowers blood calcium.

Question 29

Parathyroid hormone where produced, target tissue, function

Answer 29

Produced in the parathyroid glands, targets: bones, kidneys, and intestines, raises blood calcium levels

Question 30

estrogens where produced, target tissue, function

Answer 30

produced in ovaries, targets ovaries, breasts, uterus, stimulates uterine lining growth promotes and maintains female secondary sex characteristics.

Question 31

androgens where produced, target tissue, function

Answer 31

produced in testes, targets tetes, seminal vesicles, muscle, bone. support sperm formation promote development and maintenance of male secondary sex characteristics.

Question 32

Melatonin where produced, target tissue, function

Answer 32

Produced in pineal gland, targets brain, regulates biological rhythms

Question 33

releasing and inhibitory hormones where produced, target tissue, function

Answer 33

produced in the hypothalamus, targets and regulates anterior pituitary

Question 34

Epinephrine/norepinephrine where produced, target tissue, function

Answer 34

Produced from the adrenal medulla in the kidney, target depends, raise blood glucose levels; increase metabolic activity; constrict/dilate blood vessels.

Question 35

Glucocorticoids where produced, target tissue, function

Answer 35

Produced in the adrenal cortex in the kidney, target: skeletal muscle, liver and kidneys, raise blood glucose levels.

Question 36

Mineralocorticoids where produced, target tissue, function

Answer 36

Produced in the adrenal cortex in the kidneys, target the kidneys. Function: reabsorption of Na+ and excretion of K+. (to remember think mineral like ions chemistry)

Question 37

Insulin and glucagon where produced, target tissue, function

Answer 37

Both produced in the pancreas, and target the liver. Insulin: lowers blood glucose Glucagon: raises blood glucose

Question 38

oxytocin where produced, target tissue, function

Answer 38

produced in posterior pituitary, targets and stimulates contraction of the uterus and mammary gland cells. also targets brain

Question 39

Vasopressin (ADH) where produced, target tissue, function

Answer 39

produces in the posterior pituitary, targets: kidneys, brain. promotes retention of water by the kidneys; influences social behaviour and bonding.

Question 40

Follicle stimulating hormone (FSH) and lutenizing hormone (LH) where produced, target tissue, function

Answer 40

produced in anterior pituitary, stimulate and target ovaries and testes

Question 41

thyroid-stimulating hormone where produced, target tissue, function

Answer 41

produced in anterior pituitary, stimulates and targets thyroid gland

Question 42

Adrenocorticotropic Hormone

Answer 42

stimulates and targets adrenal cortex

Question 43

simple endocrine pathway, example?

Answer 43

endocrine cells respond directly to an internal or environmental stimulus by secreting their hormone. ex: secretin in duodenum.

Question 44

simple neuroendocrine pathway, ex?

Answer 44

stimulus is received by a neuron which stimulates a neurosecretory cell. ex: oxytocin. Basically if its from brain its neuroendocrine.

Question 45

which hormones are trophic

Answer 45

Follicle stimulating hormone (FSH), luteinizing hormone (LH), Thyroid-Stimulating Hormone (TSH), Adrenocorticotrophic Hormone (ACTH)

Question 46

how does the hypothalamus coordinate endocrine and nervous systems

Answer 46

receives info from the neurons, initiates endocrine signalling based on environmental conditions. Signals travel from the hypothalamus to the pituitary gland.

Question 47

describe the 2 lobes of the pituitary gland anterior and posterior.

Answer 47

posterior is an extension of the hypothalamus, anterior is a separate endocrine gland that produces and secretes hormones based from the hypothalamus.

Question 48

tropic hormones

Answer 48

regulate the function of other endocrine cells or glands (think tropical palm trees knocking into eachother in wind)

Question 49

nontropic hormones

Answer 49

directly act on target cells to induce effects. (straight to the point not tropical beachy fun)

Question 50

what does thyroid stimulating hormones regulate

Answer 50

blood pressure, heart rate, muscle tone, digestive and reproductive functions

Question 51

Hypothyroidism vs hypothyroidism what is it what does it cause

Answer 51

hypo: too little thyroid hormone, causes weight gain, lethargy, intolerance to colds. Hyper: high body temp, profuse sweating, weight loss, irritability, high blood pressure.