Hormones and Behaviour Flashcards
(26 cards)
what is a hormone
a chemical messenger that is released into the bloodstream and affects target cells
what are the 3 types of hormones
protein
monoamine
steroid
what are protein hormones
made up of multiple amino acids (amino acid chain) which forms a protein
what are some examples of protein hormones
insulin - energy storage
glucagon - blood sugar
ghrelin - hunger
leptin - satiety
what is a monoamine hormone
made up of a single amino acid
what is a key trick to remember the monoamine hormones
they typically end in “ine” or “in”
what are some examples of monoamine hormones
dopamine
serotonin
Norepinephrine
Epinephrine
melatonin
what are steroid hormones
made up of 3 six carbon rings and 1 five carbon ring.
released immediately into the bloodstream so not stored eg fight or flight
slow impact
where are steroid hormones produced
adrenal glands
what are some examples of steroid hormones
cortisol
testosterone
estradiol
what 2 glands produce hormones
exocrine - ducts on the body surface
endocrine - bloodstream
what are 3 differences in the communication systems of neurons and hormones
neurons:
- short distances
- rapid firing
- voluntary control
hormones:
- large distances
- hours
- no voluntary control
what are target cells
cells that have receptors for specific hormones
e.g., serotonin can only directly influence a cell that has receptors for serotonin
what 3 factors can affect the responsiveness of the target cell to hormones
- hormone concentration in the target cell
- number of target receptors on the target cell
- influence of other hormones on the target cell
what does hormone concentration mean
the amount of a hormone present when interacting with the target receptors on the target cell
what is positive feedback
a hormone release causes a further increase of that hormone
what is an example of positive feedback
contractions
- baby pushes against cervix
- stretched cervix signals brain
- brain releases oxytocin
- oxytocin causes contractions
what is negative feedback
the direction of a stimulus can be increased or decreased
what is an example of negative feedback
insulin release
- rising glucose levels after eating
- rise detected by pancreas
- pancreas secretes insulin
- insulin takes up glucose
- glucose decline
- insulin release stops
- return back to homeostasis
what is up regulation
target cell increases responsiveness of the receptor sites when hormone concentration is low
what is down regulation
target cell decreases responsiveness and loses some hormone when hormone concentration is high
do hormones cause a behavioural change
no
hormones only influence - they change the probability of a behaviour occurring but do not directly cause
bidirectional
who found that after losing a fight, male monkeys had decreased testosterone levels for a couple of days
Rose, 1971
what does Rose 1971 study on the monkey suggest
behaviour affects hormones
