Flashcards in Endocrine System Deck (75)
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1
What is the Endocrine System?
glands, tissues, and cells that secrete hormones
2
What are 2 properties of the endocrine glands?
produce hormones and lack ducts
3
List the endocrine glands
pituitary glands, thyroid gland, parathyroid gland, adrenal lands and pineal gland
4
List non-endocrine glands
hypothalamus, pancreas, ovaries and testes, and placenta
5
State the differences between Nervous and Endocrine system
Nervous: neurotransmitter, local, responds quickly, and stops quickly
Endocrine: hormones, general and widespread, responds slowly, and persist after stimulus stops
6
What are the 2 types of hormones?
amino acid-based and steroids
7
Which type of hormones are synthesized from cholesterol?
steroids
8
List hormones that are steroids
testosterone, estrogen, aldosterone, cortisol, and progesterone
9
How do hormones alter activity of target cells?
opening or closing ion channels, stimulating protein synthesis, activating or deactivating enzymes, inducing secretions, and stimulating mitosis
10
How do water-soluble hormones interact with target cells?
cannot enter target cells, act on receptors in plasma membrane, and coupled by G proteins to intracellular second messengers
11
How do lipid-soluble hormones interact with target cells?
can enter target cells, and act on intracellular receptors that directly activate genes
12
What are the steps in the cAMP signaling?
1. Hormone binds receptor
2. Receptor activates G protein
3. G protein activates adenylate cyclase
4. Adenylate cyclase converts ATP to cAMP
5. cAMP activates protein kinases
13
What non-steroid hormones also uses this mechanism?
Thyroid hormone
14
What are the steps of the intracellular receptors?
1. The steroid hormone diffuses through the plasma membrane and binds to an intracellular receptor
2. The receptor hormone complex enters the nucleus
3. The receptor-hormone complex binds a hormone response element
4. Binding initiates transcription to the gene to mRNA
5. The mRNA directs protein synthesis
15
What is up-regulation compared to down-regulation?
up-regulation increases the cell number of receptors which then becomes more sensitive to a while down-regulation reduces cell number of receptors which then becomes less sensitive to a hormone
16
What are the 3 ways that multiple hormones that act on same target?
permissiveness, synergism, and antagonism
17
Describe synergism. give an example
two or hormones act together to produce an effect that is greater then sum of their separate effects. EP and glucagon
18
Define permissiveness. Give an example
one hormone cannot exert its full effects without another hormone being present. Estrogen and progesterone
19
Define antagonism. Give an example
one hormone opposes action of another hormone. Insulin and glucagon
20
What are the three types of stimuli?
humoral, neural, and hormonal
21
How is hormone synthesis and secretion regulated?
by negative feedback
22
Which hormones respond to neural stimuli?
oxytocin, ADH, NE, and EP
23
Which hormones respond to humoral stimuli?
Calcitonin, PTH, insulin, and glucagon
24
Which hormones respond to hormonal stimuli?
ALL pituitary hormones, TH, testosterone, estrogen, and progesterone
25
What is another name for the pituitary gland?
hypophysis
26
What connects the hypothalamus to the posterior pituitary?
infundibulum
27
What is the pos. pituitary glands composed?
neural tissue
28
What is the ant. pituitary composed?
glandular tissue
29
What runs through the infundibulum and formed by axons of neurons?
hypothalamic-hypophyseal tract
30
