Endocrine System Flashcards
1
Q
Tissues are organized into _______
A
organs
2
Q
What are the 4 types of tissues?
A
Connective
Epithelial
Nervous
Muscle
3
Q
Why is it vital for cells to communicate?
A
to preserve the functions of each organ to maintain homeostasis
4
Q
What are the 6 forms of intracellular communication?
A
- Synaptic
- Juxtacrine
- Autocrine
- Direct
- Paracrine
- Endocrine
5
Q
Direct communication (2)
A
- mediated by gap junctions that contain connexins (small proteins)
- pores in the cell membrane that allow small chemical signals to move cell to cell
6
Q
Paracrine communication (2)
A
- mediated by local hormones (cytokines)
- secreted into intracellular fluid to affect nearby target cells
7
Q
Autocrine communication (2)
A
- mediated by local hormones (cytokines)
- secreted by the cell that is also the target cell
8
Q
Juxtacrine communication (3)
A
- mediated by local hormones (cytokines)
- held on the plasma membrane and target cell binds
- involved in growth and differentiation
9
Q
Synaptic communication (3)
A
- mediated by neurotransmitters
- released by presynaptic neurons that travel across a gap to a postsynatic cell
- travel long distances
10
Q
Endocrine communication (2)
A
- mediated by hormones
- secreted into extracellular fluid before entering into capillaries to travel to target cells
11
Q
Capillaries are ______
A
permeable
12
Q
All communication except for direct communication require ____
A
a target cell to express receptors made of protein
13
Q
signal transduction
A
the changes that occur between the binding of the hormone to the change that occurs when the cell is activated
14
Q
What are the 3 components of the endocrine system?
A
- produce hormones from endocrine glands or tissue
- hormones are secreted into the blood stream
- target cells have receptors for the the hormones
15
Q
endocrine vs. exocrine
A
exo: has ducts that carry secretion to the surface; the product that is released as extracellular effects
endo: no ducts; release hormones into highly permeable capillaries
16
Q
nervous system in comparison to endocrine system (4)
A
- both electrical and chemical communication
- reacts quickly
- response to long term stimulus declines
- area effected is targeted and specific
17
Q
endocrine system in comparison to nervous system (4)
A
- only chemical
- reacts slowly (effects continue for weeks)
- response to long term stimulus persists
- area effected is general and widespread
18
Q
several chemicals function as _____ and _____
A
hormones and neurotransmitters
19
Q
neuroendocrine cells
A
neurons that secrete hormones
20
Q
What is controlled by the endocrine system (7)
A
- reproduction
- growth
- development
- activation of body defenses
- salt and water balance
- nutrient balance
- cellular metabolism
21
Q
10 major endocrine organs
A
- hypothalamus
- pituitary gland
- pineal gland
- thyroid gland
- parathyroid gland
- thymus
- adrenal gland
- pancreas
- ovaries
- testes
22
Q
hypothalamus
A
the control center of the endocrine system (sensory, emotional, and outside/inside connections)
23
Q
What are the 3 roles of the hypothalamus?
A
- release of hormones that control anterior pituitary
- produces and controls the release of oxytocin and ADH
- controls the release of E and NE from adrenal medulla
24
Q
pituitary gland is also known as _______
A
hypophysis
25
Where is the pituitary gland located?
in the sella turcica of sphenoid bone
26
What are the 2 parts of the pituitary gland?
- anterior (adenohypophysis)
| - posterior (neurohypophysis)
27
Where does the adenohypophysis arise from? neurohypophysis?
outgrowth of the pharnyx (hypophyseal pouch); the brain
28
portal system
two capillary beds in a row
29
hypothalamo-hypophyseal portal system
hypothalamus and anterior pituitary have vascular connection
30
trophic hormones
target other endocrine glands
31
What are the 4 trophic hormones? (all in the anterior lobe)
- FSH (follicle stimulating hormone)
- LH (luteinizing hormone)
- TSH (thyroid stimulating hormone)
- ACTH (adrenocorticotropic hormone)
32
gonadotropins? (2)
FSH and LH
33
What are the 2 non trophic hormones?
- PRL (prolactin)
| - GH (growth hormone)
34
FSH (3)
follicle stimulating hormone
- secreted by the gonadotropic cells
- stimulates production of egg and sperm cells
35
LH (3)
luteinizing hormone
- secreted by the gonadotropic cells
- stimulates hormone production (females: progesterone and estrogen) (males: testosterone)
36
TSH (3)
thyroid stimulating hormone
- secreted by thyrotropes
- stimulates growth of gland and secretion of TH (T3 and T4)
37
ACTH
adrenocorticotropic hormone
| -regulates response to stress (adrenal cortex)
38
corticosteroids (2)
- regulate energy in the body during stress
| - from adrenal cortex regulates glucose, fat and protein metabolism
39
PRL (3)
prolactin
- secreted by lactotropes
female: milk production after delivery
male: increase LH' thus increasing testosterone
40
What hormone is released after an orgasm giving a calming effect?
prolactin
41
GH (4)
growth hormone
- promotes tissue growth
- mitosis and cellular differentiation
- stimulates the liver to produce somatomedins
42
GH: protein synthesis
increase DNA transcription for increase of mRNA production
43
GH: lipid metabolism
stimulates free fatty acids and glycerol release from adipocytes
44
GH: CHO metabolism
glucose sparing for nervous system
45
GH :electrolyte balance
promotes salt retention
46
GH: childhood and adolescence (3)
GH is at its highest
bone, cartilage, and muscle growth
stimulates growth of epiphyseal plate
47
GH: Adulthood
increase osteoblastic (building) activity and appositional (width) growth
48
______ fluctuate throughout the day? When are they highest? lowest?
GH
highest: during deep sleep and high protein meal
lowest: after high CHO meal
49
posterior pituitary
contains a collection of axons
50
The paraventricular nucleus in the hypothalamus releases _____; while the supraoptic nucleus releases _____
oxytocin; antidiuretic hormone (ADH)
51
ADH
target the kidneys to increase water retention
52
Oxytocin (2)
labor contractions and lactation in females
| sperm transport in males
53
anterior lobe control is determined via ______ while posterior lobe control is determined via ____
hormones; reflexes (timing)
54
suckling infant->stimulate nerve endings->hypothalamus->_______->________->milk secretion
posterior lobe; oxytocin
(positive feedback)
-higher brain centers start process early
55
dehydration increases osmolarity of blood; _____ is released
ADH (water retention)
56
pineal gland (3)
produces serotonin in the day and melatonin at night
receives input from the retina
regulate timing in puberty
57
thymus
superior to the heart
| secretes hormones to regulate development of T-lymphocytes
58
thyroid gland (2)
largest endocrine gland; high rate of blood flow
| triggers release of GH
59
colliod
a suspension of amino acids
60
C cell
calcitonin produced that decrease Ca in blood; bone formation
61
PTH
increases blood Ca levels
| promotes synthesis of calcitriol by kidneys
62
Adrenal Medulla origin? Cortex?
neural in origin; epithelial
63
adrenal medulla?
sympathetic (fight or flight) ganglion that consists of chromaffin cells
64
chromaffin cells
modified neurons (no projections)
65
What does the adrenal medulla stimulate?
the release of catacholamines (E, NE, and a little dopamine)
66
Stress causes medullary cells to stimulate ______
cortex
67
3 layers of adrenal cortex
```
zona glomerulosa (outer)
zona fasciculata (middle)
zona reticularis (inner)
```
68
zona glomerulosa (3)
mineralocorticoids
- control electrolyte balance
- aldosterone promotes (3)Na+ retention and (2)K+ excretion
69
zona fasciculata (3)
glucocorticoid
- allows the body to deal with stress and heal
- stimulates fat and protein catabolism
70
zona reticularis (2)
sex steroids
| -promotes testosterone in females
71
pancreatic endocrine hormones
islets
72
insulin in pancreatic hormones (5)
```
beta cells
secrete after CHO meal and increase Glu levels
stimulate Glu and amino acid uptake
nutrient storage
antagonize glucagon
```
73
glucagon in pancreatic hormones (2)
alpha cells
| secrete during fasting (between meals) or low CHO and high protein diets
74
somatostatin in pancreatic hormones
delta cells
| secrete with rise in blood Glu and amino acids after meal
75
hyperglycemic hormones raise blood glucose (5)
```
GH
E
NE
glucagon
glucocortiocoid (zona fasciculata)
```
76
hypoglycemic hormoes lower blood glucose (1)
insulin
77
follicles of the ovaries are surrounded by _______
granulosa cells
78
granulosa produces what during the first half of the menstrual cycle
estradiol
79
corpus luteum
forms from the follicle after ovulation
| produces estradiol and progesterone
80
What are the purposes of estradiol and progesterone? (3)
development of female reproductive system
regulate menstrual cycle, sustain pregnancy
prepare mammary glands for lactation
81
the ___ ___ in the testes produce testosterone and estrogen
interstitial cells
82
What is the function of testosterone? (2)
development of male reproductive system
| sustain sperm production and sex drive
83
What are 6 other organs with endocrine functions?
```
heart
kidney
skin
liver
stomach and intestines
placenta
```
84
What 3 classes can hormones be classified in?
lipid
amino acid
peptide
85
lipid derivatives of hormones (2)
eicosanoids (derived from arachidonic acids)
| steroid (similar to cholesterol)
86
amino acid derivatives of hormones (2)
tyrosine
| tryptophan
87
tyrosine and be divided into _____ and ______
```
thyroid hormone (2 tyrosines; dipeptide)
catecholamines (monoamines)
```
88
monoamines and peptides are _______; they are transported via _____
hydrophilic; blood
89
steroids and thyroid hormones are _____; they must be ____ to be transported
hydrophobic; bound
90
bound hormone
protects hormone from enzyme and kidney infection
91
unbound hormone
leaves capillaries to reach the target cell
92
transport proteins in blood:
albumin, thyretin, and TGB bind to _____
steroid hormone binds to _______
aldosterone _____
thyroid hormone
globulins
no transport protein
93
humoral stimuli
changing blood levels to control hormone release
94
neural stimuli
nervous system
| sympathetic and parasympathetic influence to control hormone release
95
hormonal stimuli
positive and negative feedback to control hormone release
96
dropping of blood Ca levels stimulates what?
| This is an example of _____ stimuli
parathyroid hormone
| humoral
97
Oxytocin (suckling of baby) is an example of ____ stimuli
neural
98
Control of thyroid hormone release is an an example of ____ stimuli
hormonal
99
hormone receptors can be found both ___ and ____
on the surface and intracelluarally
100
hydrophobic hormones bind where
penetrate the plasma membrane and enter the nucleus (intracellular)
101
hydrophilic hormones bind where
bind to the cell surface receptors
102
Example of Thyroid Hormone
With hydrophobic hormones the hormone passes through the plasma membrane into the nucleus to bind receptors forming the ______. This then ____ into ____. Basically ____ ____ happens
hormone receptor complex; translocates; DNA; gene activation
103
What other effects does TH have (2)
bind to mitochondria receptors- increase aerobic respiration
| bind to ribosomes-increase protein synthesis
104
Steps for second messenger system for hydrophilic hormones (5)
1. hormone binds activate G protein
2. G protein binds GTP
3. produce cAMP
4. Activates PKA
5. Activates enzymes
105
What are some metabolic reactions that can occur from second messenger system? (4)
change protein synthesis
activate or inactivate enzyme
trigger secretion
change membrane potentials
106
How can you trigger the termination of signal for hydrophilic hormones? (3)
stop release of hormone
deactivate G protein by hydrolysis
breakdown cAMP
107
What are some advantages for second messenger system? (3)
amplification
regulation
cross talk between systems
108
UP regulation includes (2)
increase synthesis of receptors
| reduce rate of degradation of receptors
109
DOWN regulation includes (2)
reduce synthesis of receptors
| increase rate of degradation of receptors
110
What types of effects can hormones have when they interact?(3)
permissive
synergistic
antagonistic
111
permissive effects
additive; 2 dif hormones using the same second messenger system
112
synergistic effects
exponential; 2 dif hormones using dif second messenger systems
