hormones

Question 1

what are the levels of physiology regulation?

Answer 1

intracellular
local regulation
extrinsic regulation
endocrine activity

Question 2

what is intracellular regulation?

Answer 2

regulation of enzyme catalysed reactions

Question 3

what is a local regulation?

Answer 3

auto-regulation, intrinsic (heart)

Question 4

what is a extrinsic regulation?

Answer 4

reflex neural activity

Question 5

what is a endocrine activity?

Answer 5

only target cells with appropriate receptors respond

Question 6

what are the 4 1st messenger controls?

Answer 6

autocrine control
paracrine control
endocrine control
neurocrine control

Question 7

define autocrine control

Answer 7

within cell or between the same types of cell (rapid diffusion)

Question 8

what is paracrine control?

Answer 8

cell to cell within diffusion range (rapid diffusion)

Question 9

what is endocrine control?

Answer 9

Cell to cell via slow diffusion OR transport system

Question 10

what is neurocrine control?

Answer 10

nerve to nerve (rapid diffusion)

Question 11

example of a quick regulation

Answer 11

neural control

Question 12

example of a moderate regulation response

Answer 12

hormone

Question 13

example of a long term regulation

Answer 13

genetical

Question 14

explain how endocrine hormone works

Answer 14

1) Endocrine cell produces hormones
2) Hormone released into blood stream (transport mechanism)
3) Hormone only react with specific hormone receptor on distant target cell

Question 15

explain how paracrine hormones work

Answer 15

1) Paracrine cells secrete hormones into the immediate extracellular environment to the nearby target cell

Question 16

explain how autocrine hormones work

Answer 16

1) Autocrine cells produce hormones and secrete into extracellular environment.
2) The hormone binds to the SAME autocrine cell surface receptors to initiate signal transduction (cell signalling)

Question 17

explain how steroid hormones create new mRNA strands

Answer 17

1) In the blood steroid hormones are bound to plasma protein carriers.
2) Plasma protein carriers unbound to hormone when near the lipid permeable membranes
3) Steroid hormones bind to steroid hormone receptors which are in the cytoplasm or nucleus
4) The receptor – hormone complex binds to DNA and activates or represses one or more genes.
5) Activated genes create new mRNA that moves back to the cytoplasm
6) Translation produce new proteins or cell processed
7) Some steroid hormones also bind to membrane receptors that use second messenger systems to create rapid cellular response.
8) This creates new mRNA

Question 18

why can steroid hormones get through lipid permeable membranes?

Answer 18

because they are lipid soluble

Question 19

why do steroid hormones need plasma protein carriers in the blood?

Answer 19

because they are hydrophobic

Question 20

what do steroid hormones cause?

Answer 20

long term changes as it is changing the overall activity of DNA and producing new mRNA strands

Question 21

what are 2nd messengers?

Answer 21

Second messengers are small intracellular molecules that mediate (heighten) the effects of first messengers.

Question 22

two examples of 2nd messengers

Answer 22

neurotransmitters and hormones

Question 23

what is the role of second messengers?

Answer 23

Second messengers serve to greatly amplify the strength of the signal. Binding of a ligand to a single receptor at the cell surface may end up causing massive changes in the biochemical activities within the cell.

Question 24

what are the 3 major classes of second messengers?

Answer 24

• cyclic nucleotides (e.g., cAMP and cGMP)
• inositol trisphosphate (IP3) and diacylglycerol (DAG)
• calcium ions (Ca2+)