Hormones Flashcards
What is the endocrine system?
secretes hormones that coordinate slower, but longer-acting responses including: reproduction, development, growth, metabolism, behavior
What is the nervous system?
high speed electrical signals along specialized cells (neurons) that regulate/control other cells
How do cells detect hormones?
They have receptors that fit a specific signaling molecule or ligand
What are hormones? What are the types?
secreted chemical messages
they are steroids, amines, and peptide chains/proteins
What is endocrine?
hormones distributed in circulatory system that reach target cells by entering the bloodstream
What is paracrine?
“local regulators” that act on neighbor cells
they are signaling molecules that are not produced by glands, but are secreted from cells in tissues in response to stimuli
move by diffusion and trigger rapid responses
also called prostaglandins
What is autocrine?
secreting cells are themselves the target
they are signaling molecules that are produced by a cell, and then are self-detected by receptors on the cell’s own membrane
What is a neurotransmitter?
signaling molecules secreted by membrane regions where neurons interact, called synapses
secreted directly by neurons into the space between cells (synapse)
diffuse short distance to target cell, rapidly
What are neurohormones?
neuronal hormones that enter blood
used in neuroendocrine signaling, in which neurons release hormones so they can leave the brain and regulate large functions like water balance and temperature
What are pheromones?
hormones secreted from glands that act outside of an organism’s body
What are water soluble hormones?
do not pass easily through membranes, so receptors are on outer membranes
amines and polypeptides
What are lipid soluble hormones?
pass easily through cell membranes, so receptors are often inside the target cell
steroids
What are the three key events in hormone signaling?
Reception
Migration
Response
What is the hypothalamus?
major endocrine signaling center in vertebrate brain
it receives neuron signals and releases neurohormones via neurosecretory cells
instructs the pituitary gland to release hormones into the body
What is the posterior pituitary gland?
stores and secretes hormones that are made first in the hypothalamus
ADH moves from hypothalamus to posterior pituitary which is stored there until additional signals are received