Hormones

Question 1

what is the endocrine system

Answer 1

endocrine glands release chemical substances called hormones into bloodstream affecting target organs

Question 2

compare endocrine gland to nervous system

Answer 2

slower action
general
act for long times

Question 3

what are the 5 glands and what hormones do they produce

Answer 3

pituitary - master gland produces FSH AND LH
thyroid gland - thyroxine to regulate metabolic reaction / heart rate
ovaries - produce oestrogen in menstrual cycle
testes - produce testosterone sperm and puberty
pancreas - produces insulin control glucose
adrenal gland - adrenaline for flight or fight

Question 4

what processes does adrenaline activate

Answer 4

adrenaline binds to heart receptors to cause more contraction with more force to increase blood pressure and heart rate

this causes more blood flow to muscles receiving more oxygen and glucose for respiration

adrenaline binds to liver cells to stimulate break down of glycogen to release glucose

increases glucose levels so more transported to cells

when stressful situation send elecctrical impulse to adrenal to release adrenaline

Question 5

what is negative feedback

Answer 5

when body detects change in substance above/below normal triggering response to bring back to normal

Question 6

explain the negative feedback of thyroxine

Answer 6

when thyroxine levels are low hypothalamus stimulates TRH
TRH stimulates Pituitary gland to stimulate TSH
TSH stimulates thyroid gland to release thyroxine which rises back to normal

when thyroxine is high TRH is inhibited so TSH is not produced hence thyroxine falls