Hormonal control of metabolic rate Flashcards
what is your metabolic rate?
the rate at which the energy stored in your food is transferred by all the reactions that take place in your body to keep you alive
what are the conditions needed to measure your metabolic rate?
body at rest
warm room
long after the person last had something to eat
name a hormone that affects metabolic rate and where is it released from?
thyroxine
thyroid gland
how does thyroxine affect metabolic rate?
increases heart rate
increases rate at which proteins and carbohydrates are broken down inside cells
the amount of thyroxine produced is controlled by the thyroid gland and what other two glands?
pituitary
hypothalamus
why is the control of thyroxine concentration in the blood an example of negative feedback?
an increase in thyroxine concentration directly causes changes that cause a decrease in the amount of thyroxine released into the blood etc
what is adrenalin?
a hormone released from the adrenal glands
compare the release of adrenalin in normal conditions and in frightening / exciting situations
normal: very little released into the blood
other: large amounts into the blood
what causes the release of adrenalin?
an increase in impulses to the adrenal glands
what is the target organ for adrenalin?
liver
what does adrenalin in the liver lead to ?
increase of glucose in the blood
what is glycogen?
a polymer made of glucose molecules
what is glucose needed for and why?
to provide additional glucose for respiration therefore releasing energy
what effect does adrenalin have on the heart?
increase in heart rate
what is the response called from adrenalin?
fight or flight
