Endocrine Physio

Question 1

Endocrinology
- Classic vs Modern definition
- Information theory

Answer 1

Classic: Branch of physiology concerned w/ the structure, function, and disorders of the endocrine glands

Modern: Study of structure, function and evolution of the chemical signals that transmit info from one region of the organism to another

Information theory: When there’s a signal sent/received, there is info sent to change something in the environment (not just a downstream signal from receptor to receptor)

Question 2

Factors of definitions for signalling molecules (4)

Answer 2

1) Signal ability
2) Structure
3) Type of receptor binding
4) Expression pattern

Question 3

Autocrine
Paracrine
Juxtacrine
Intacrine
Endocrine
Neurocrine
Neuroendocrine
Exocrine
Cytocrine

Answer 3

Autocrine: Signals the modulate the action of the cell they’re secreted from
Paracrine: Signals the modulate nearby cells
Juxtacrine: Non-secreted membrane bound signals that attach to a similarly bound receptor on a juxtaposed cell
Intacrine: Non-secreted signals that module organelles within a cell
Endocrine: Secreted signals that are released into a vascular system (hormones)
Neurocrine: Chemical signals transmitted from one neuron to another
Neuroendocrine: Signals produced in the nervous system that are released into the vascular system
Exocrine: Signals that are released exterior to an organism to modulate the actions of other individual organisms
Cytocrine: Signals released typically by the mobile cells in the vascular system (white blood cells)

Question 4

Neurotransmitter
Neuromodulator
Releasing factor
Neurohormone
Tropic (trophic) hormones
Hormones

Answer 4

Neurotransmitter: Chem signal that stimulates an action potential between neurons
Neuromodulator: Chm signal that modifies the efficacy of the action potential
Releasing factor: Chem signal from the brain that stimulates the release of hormones from neuroendocrine or endocrine glands
Neurohormone: Chem released by the brain into blood stream (ex: oxytocin)
Tropic (trophic) hormones: Neurohormones that have a physiological action on non-neural tissues
Hormones: Chem released from a non-nervous gland or tissue into blood stream

Question 5

Evolution of signalling pathways:
- Nervous
- Neuroendocrine
- Endocrine

Answer 5

Sensory input -> Sensory cell -> Ionic coupling w/ a locomotor cell w/ cilia
—
Sensory input -> Sensory cell releases chemical secretion and paracrine diffusion
—
Sensory input -> Sensory cell releases chem secretion and paracrine diffusion -> Received by non-nervous depolarizing cell to secrete