16) Endocrine System Flashcards
1-22 quiz, 23-75 lecture notes
1
Q
the condition produced by factors that tend to cause changes is the body’s internal environment and threaten its survival is called ________.
A
stress
2
Q
the sex hormones from the adrenal cortex are primarily ___
A
androgens
3
Q
the ________ gland is located deep between the cerebral hemisphere attached to the roof of the third venticle
A
pineal
4
Q
the central portion of the adrenal gland is the adrenal ________
A
medulla
5
Q
________ hormone acts primarily on the kidneys and causes them to conserve water.
A
antidiuretic
6
Q
adenylate cyclase causes ATP molecules to become ________ molecules
A
cyclic AMP
7
Q
________ stimulates the activity of bone-resorbing osteoblasts.
A
calcitonin
8
Q
the pancreas functions as part of the endocrine system and as a part of the ________ system.
A
digestive
9
Q
the thyroid gland has a special ability to remove ________ from the blood.
A
Iodine
10
Q
a person under stress may have a lowered resistance to ________.
A
infection
11
Q
aldosterone
A
electrolyte balance
12
Q
thymosin
A
maturation of T cells
13
Q
prolactin
A
milk production
14
Q
cortisol
A
stress maintenance
15
Q
thyroid hormone (TH)
A
metabolism
16
Q
adrenocorticotropic hormone (ACTH)
A
release of cortisol, and during extreme stress other adrenal hormones as well
17
Q
insulin
A
reduces blood sugar
18
Q
follicle stimulating hormone (FSH) and luteinizing hormone (LH)
A
regulation of sex cells
19
Q
glucagon
A
increases blood sugar
20
Q
oxytocin
A
uterine contractions and milk letdown
21
Q
parathyroid hormone (PTH)
A
blood calcium regulation
22
Q
antidiuretic hormone (ADH)
A
water balance
23
Q
glands
A
one or more cells that secrete substances
24
Q
exocrine glands
A
secrete their products through tubes or ducts to external body surfaces
25
endocrine glands
release substances into the extracellular spaces surrounding endocrine glands, travel through the blood to specific target cells
26
paracrine hormones
short-distance chemical signal that regulates neighboring cells
27
autocrine hormones
short-distance chemical signals that exert their effects on the same cells that secretes them
28
nervous system effect on endocrine system
*sends impulses to specific cells (usually muscle or glands)
*signals are rapid, but can be brief unless neuronal activity continues
29
endocrine system
*use chemical messengers - glands release hormones into blood stream, only affect receptors on target cells
*response can last days, even if secretion ceases.
30
major endocrine glands
*hypothalamus
*pituitary gland
*thyroid gland
*adrenal glands
*pancreas
31
hormone chemistry
*can altering metabolic processes
*can alter enzyme activity, or rate of transport of substance
*delivered by binding to receptors on target cell
32
upregulation
increase in number of receptors on target cell, in response to a decrease in hormone level
33
downregulation
decrease in number of receptors on target cell, due to an increase in hormone level
34
steroid hormones
*lipids delivered from cholesterol
*can enter target cells by diffusion
*include sex hormones' (testosterone and estrogen)
35
actions of steroid hormones
*cross cell membranes, combines with receptors in nucleus
*become hormone receptor complex, attach to DNA, inhibiting or activating gene transcription
*synthesis of mRNA is activated, protein synthesized
36
nonsteroid hormones
*usually soluble and cannot cross the plasma membrane
*(e.g. amines, proteins, peptides, glycoproteins)
37
actions of nonsteroid hormones
*messenger binds to protein receptors on targeted cell membrane
*protein receptor has a binding site and activity site, unite with binding site
*activity site reacts with other membrane proteins, adenylate cyclase changes ATP into cyclic AMP, cAMP promotes series of reactions.
38
cellular changes caused by cAMP
*alter membrane permeability
*activate enzymes
*promote protein synthesis
*stimulate or inhibit metabolic pathways
*initiate secretion of hormones
39
control of hormone secretion
primarily controlled by Negative Feedback Mechanisms
40
negative feedback mechanism
*when the endocrine gland or system is sensitive to concentration of substances it regulates, or product from a process it regulates
*when concentration reaches a certain level, the gland is inhibited and activity decreases
*three methods (tropic hormones, nervous system control, changes in composition of internal environment)
41
pituitary gland
*located at the base of the brain in the sella turcica (sphenoid bone)
*approx. size and shape of kidney bean
*anterior lobe & posterior lobe
42
pituitary gland (anterior lobe)
*hypothalamus stimulates anterior pituitary gland to release hormones
*hormones' of anterior lobe: growth hormone, prolactin, thyroid secreting hormone, adrenocorticotropic hormone, follicle-stimulating hormone, luteinizing hormone
43
growth hormone (GH)
*stimulate bone and muscle growth
*enhances movement of amino acids through the cell membrane and increases the rate of protein synthesis
44
prolactin (PRL)
*stimulates milk production in females
*throught to help maintain normal sperm count in males
45
thyroid secreting hormone (TSH)
*controls secretions of hormones from thyroid
46
adrenocorticotropic hormone (ACTH)
*controls the secretion of some hormones from adrenal cortex
47
follicle-stimulating hormone (FSH)
*in females, stimulates development of egg containing follicles in ovaries, stimulates follicle cells to secrete estrogen
*in males, stimulates production of sperm cells
48
luteinizing hormone (LH)
*promotes secretion of sex hormones in males and females
*stimulates release of egg from ovary
49
pituitary gland (posterior lobe)
*does not produce hormones, neurosecretory cells secrete two hormones that are produced by the hypothalamus directly to blood vessels that are located in the posterior lobe
*hormones include; antidiuretic hormone and oxytocin
50
antidiuretic hormone (ADH)
*keep blood volume constant by reabsorption of water in kidneys
51
oxytocin (OT)
*stimulates uterine contraction
*stimulates mammary glands to release milk
52
thyroid
*located on trachea just below larynx
*responsible for removing iodine from the blood
*produces three hormones: thyroxine (T4), triiodothyronine (T3), calcitonin
53
thyroxine (T4) and triiodothyronine (T3)
*increase rate of energy released from carbohydrates
*increase rate of protein synthesis
*accelerates growth, stimulates activity in nervous system
*controlled by (TSH)
*T3 is 5X more potent
54
calcitonin
*lowers blood calcium and phosphate ion concentrations by inhibiting release of calcium and phosphate from bone
*increases rate at which calcium and phosphate are deposited in bone
55
parathyroid gland
*located on the posterior surface of the thyroid gland
*secretes parathyroid hormone (PTH)
56
parathyroid hormone (PTH)
*increases blood calcium levels
*stimulates the kidneys to retain calcium and excrete phosphate
*promotes calcium absorption from food into small intestines
57
adrenal glands
*suprarenal glands, located above the kidneys
*functions as two separate endocrine glands: andrenal medulla, and adrenal cortex
58
adrenal medulla
*secretes epinephrine and norepinepherine
*controlled by sympathetic NS- dilates respiratory passages, increases heart rate and blood pressure
*helps body respond to stress- increases blood pressure, heart beat, breathing rate, dilates pupils, inhibits digestion
59
adrenal cortex
*secretes more than 30 different steroids including: aldosterone, cortisol, adrenal androgens
*has three zones, each producing different types of hormones: zona glomerulosa, zona fasciculata, zona reticularis
60
aldosterone
*increases blood volume and pressure by promoting conservation of sodium ions and eliminating potassium ions through process of retaining water by osmosis
61
cortisol
*keep blood glucose levels within a normal range between meals: *decreases protein synthesis
*increases fatty acid release from adipose tissue
*stimulates glucose synthesis from non-carbohydrates (amino acids and glycerol)
62
adrenal androgens
*supplement sex hormones from the gonads in males
*can covert into estrogen by skin, liver, adipose tissue in females
63
zona glomerulosa of adrenal cortex
*outer zone
*produces aldosterone and other mineralocorticoids
64
zona fasciculata of adrenal cortex
*middle zone
*produces cortisol and other glucocorticoids (anti-inflammatory and help with metabolism)
65
zona reticularis
*inner zone
*produces male sex hormones
66
pancrease
*act as an exocrine gland- produces digestive enzymes
*acts as an endocrine gland- produces hormones
*types of pancreatic cells: pancreatic Islets, alpha cells, beta cells, delta cells
67
alpha cells
*secrete glucagon
*triggers breakdown of glycogen to glucose when body needs energy
68
beta cells
*secrets insulin
*promotes formation of glycogen from glucose
*inhibits conversion of non-carbohydrates into glucose
*enhances movement of glucose into adipose and muscle cells
69
delta cells
*secretes somatostatin
*helps regulate glucose metabolism by inhibiting secretion of glucagon and insulin
70
pineal gland
*secretes melatonin
*light causes decrease of melatonin and dark increases production
*maintains internal clock, sleep-wake cycle
71
thymus gland
*secretes thymosin
*promotes development of certain lymphocytes (T cells)
72
reproductive glands
*females: ovaries secrete estrogen and progesteron
*placenta secretes estrogen, progesteron, and gonadotropins
*males: testes secrete testosterone
73
stressor
any stimulus that directly or indirectly causes hypothalamus to initiate stress-compensating responses
74
short-term stress
*hypothalamus activates the adrenal medulla via neural stimulation,
*adrenal medulla secrets epinephrine (80%) and norepinephrine (20%), readies body for "fight or flight"
* HR & BP increase, bronchioles dilate to facilitate flow of air in and out lungs, BGL and metabolic rate increases
75
long-term stress
*hypothalamus activates the adrenal cortex via hormonal stimulation, which greatly reinforces short-term response
*cause hypothalamic neurons release corticotropin hormone (CRH) *anterior petuitary cells release adrenocorticotropic (ACTH)
*metabolic effect: break down protein to increase blood amino acids, increases blood sugar by converting glycogen to glucose, break down fat, increase fatty acids for muscles
*renal effect: kidneys retain sodium, cause water retention, blood volume and pressure rise
