Endocrine System and Hormones Flashcards
Berthold’s experiment
remove the testes on roosters
group 1; kept testes and developed normally
group 2; testes removed
group 3; testes removed but then one put back in the cavity
conclusions of Berthold’s experiment
group 1 and 3 developed normally, group 2 did not develop normal comb, mounting, aggressiveness, and crowing
testes given back in adulthood did not give back traits
testes are giving a “secretory blood-borne chemical” and they only have developmental effects in a certain time-frame
hormones are released..
- by glands
- into the bloodstream
- by animals
there are exceptions
neurocrine definition
neural communication using neurotransmitters between neurons
endocrine definition
hormone release inside the body and the bloodstream. not as targeted as NTs
autocrine definition
cell releases hormones that latch to receptors on itself and creates a feedback loop
paracrine definition
localised hormone release that has a the strongest effect on the closest cells
pheromones definition
within species signaling molecules being sent outside the body
allomones definition
inter species signaling molecules released between organisms
exocrine definition
out of body hormone secretion
e.g. sweat glands, tear glands
Principle hormone functions
- slow acting
- change behaviour intensity or probability
- behaviour affects hormone release and vice versa
- multiplicity of action; have variety of targets and therefore a variety of effects
- pulsatile and rhythmic secretion
- interaction that has unique effects
- need receptors
what is lacking from artificial hormone injections?
pulsatile and rhythmic secretion, instead it happens all at once
why are hormone effects more slow acting?
they travel through the bloodstream and therefore are much slower than neuronal transmissions
what is the hypothalamus a junction between?
the nervous system and the endocrine system
