Ch. 17 Endocrine System Flashcards
(115 cards)
1
Q
What classes are there for hormones?
A
There are water soluble and fat soluble hormones
2
Q
What are examples of water soluble hormones?
A
Amines: (Catecholamines) dopamine, epinephrine, norepinephrine
Peptides and proteins: insulin, glucagon, hypothalamus hormones, anterior pituitary hormones
3
Q
What are examples of fat soluble hormones?
A
Thyroid hormones: are amines but are not soluble in water
Steroids: testosterone, estrogen, progesterone, aldosterone, cortisol (derived from cholesterol)
4
Q
Where are Thyroid hormones stored?
A
thyroid gland
5
Q
Where are Epinephrine and norepinephrine stored?
A
adrenal medulla
6
Q
Where is dopamine stored?
A
hypothalamus
7
Q
is it epinephrine or norepinephrine that adrenal medulla produce more?
A
epinephrine
8
Q
What would epinephrine and norepinephrine be called if they are released from neurons?
A
neurotransmitters, but neurons release more norepinephrine
9
Q
Where are thyroid hormones made from?
A
They are made from tyrosine (amino acid)
10
Q
Where do thyroid hormones diffuse out into?
A
They diffuse out of thyroid gland cells into blood and are not
packaged into vesicle because they are fat soluble
11
Q
How do steroid hormones made from cell end up going into blood?
A
Steroid are transported from cell to interstitial fluid and it goes to blood because they are fat soluble so they can move through membrane
12
Q
What do steroids have to be transported through?
A
through blood on plasma protein albumin
13
Q
What is pituitary gland protected by?
A
sella turcica of sphenoid bone
14
Q
What are hypothalamus and pituitary are connected by?
A
infundibulum that is containing axons and blood vessels
15
Q
What does posterior pituitary store?
A
hormones made by hypothalamus (in axon terminals): oxytocin and ADH
16
Q
When does anterior pituitary make hormones?
A
when stimulated by hypothalamus tropic hormones
17
Q
What do Capillaries in median eminence form?
A
hypothalamo-pituitary portal vessels
18
Q
What is it there between hypothalamus and anterior pituitary?
A
there is direct blood connection
19
Q
What hormones does posterior pituitary synthesize?
A
posterior pituitary does not synthesize any hormones; it only secretes them
20
Q
What is oxytocin involved in?
A
involved in uterine contractions, milk ejection in nursing mothers, emotional bonding, love, empathy, and feeling socially connected
21
Q
What does Antidiuretic hormone (ADH), also called vasopressin, cause?
A
causes kidneys to reabsorb water and causes vasoconstriction to increase blood pressure when blood volume is low
22
Q
What is posterior pituitary stimulated by and what increases water excretion?
A
stimulated by low blood pressure and diuretic increases water excretion
23
Q
What does Bone growth (height) of Growth Hormone and IGF-1 in children and adolescents cause?
A
causes calcium to be incorporated into bone during exercise (decreases osteoporosis in adults)
24
Q
What does protein synthesis of Growth Hormone and IGF-1 particularly occur in?
A
particularly occur in skeletal muscle (required to increase
muscle strength)
25
Q: What is result of GH on metabolism?
GH causes liver to break down glycogen and fat, leading to increase in blood sugar levels This process provides fuel for cells that are growing
26
What does stress inhibit while Growth Hormone and IGF-1 stimulate immune system
Stress hormones inhibit growth
hormone and inhibit immune system
27
What is Cell rejuvenation?
anti-aging hormone
28
What do Growth hormone and insulin-like growth factors of Hypothalamus and Pituitary do?
They stimulate cell division, promote bone growth, promote protein synthesis mostly in muscle, break down fats for energy, and decrease the effects of insulin
29
What is Thyroid hormones required for?
required for synthesis of growth hormone
30
What does insulin stimulate and inhibit?
stimulates nutrient storage, inhibits protein breakdown
31
What does Sex hormones stimulate?
Sex hormones (testosterone, estrogen) stimulate GH and IGF, and protein synthesis
32
What does Cortisol inhibit?
Cortisol inhibits growth
33
What is mitogen?
molecule that stimulates cell division
34
In what response does anterior pituitary gland produce thyroid-stimulating hormone
(TSH)?
in response to secretion of thyroid-releasing hormone (TRH) from hypothalamus
35
How is TSH regulated and what stimulates the release of TRH?
TSH is regulated by negative feedback from thyroid hormones in blood
Low levels of T3 and T4 stimulate release of TRH, which in turn stimulates release of TSH from pituitary gland
36
In what response does anterior pituitary gland release adrenocorticotropic hormone
(ACTH)
in response to secretion of corticotrophin-releasing hormone (CRH) from hypothalamus
37
What does ACTH acts on adrenal cortex regulate?
production of glucocorticoids, mainly cortisol, in response to stress
38
Why does ACTH cause cortisol?
to be produced from cholesterol by zona fasciculata region of adrenal cortex
39
What important roles do FSH and LH have?
They have important roles in stimulation of the gonads during puberty and reproduction
40
What is FSH?
primary hormone that stimulates development of sperm in testes and oocytes in ovaries
41
What does LH stimulate?
stimulates gonads to produce hormones testosterone, estrogen, and progesterone
42
What enzyme that female have more and what does it do?
females have much more of aromatase enzyme that converts testosterone into estrogen
43
In what response is Prolactin (PRL) produced in anterior pituitary gland and released?
in response to secretion of prolactin-releasing hormone (PRH), which is produced in hypothalamus
44
What is primary role of prolactin?
lactation; it stimulates growth of female mammary glands and production of milk
45
What is other role of prolactin?
surfactant production in fetus at end of the pregnancy, and it helps mother’s immune system not reject infant
46
What and where is thyroid stimulated by?
By TSH to produce T3 (tiiodothyronine) and T4 (thyroxine) in follicular cells
47
Why is Iodine require?
Iodine (available in iodized salt) is required to make thyroid hormones
48
What is main role of Thyroid?
Main role is to regulate metabolism – increases cells’ utilization of oxygen, breaks down fats and glycogen to make ATP
49
What is selenium very important micronutrient?
It is required for thyroid hormone synthesis, and selenium deficiency can cause severe thyroid malfunction
50
What is iodine co-transported into follicular cells with and where would iodine diffuse into?
with sodium (Na+ moved back out by Na+/K+ pump), then iodine diffuses into colloid (centre of follicles)
51
What protein does colloid contain?
thyroglobulin
52
In colloid, what is iodine attached to?
attached to tyrosine (amino acid) by enzyme called thyroid peroxidase and attached to thyroglobulin
53
What can iodine form?
Iodine can form either monoiodotyrosine (MIT) or diiodotyrosine (DIT); then if two DIT molecules are combined T4 is formed – a MIT + DIT = T3
54
What does thyroid hormones do When thyroid hormones are needed?
they move from follicle lumen into follicular cells by endocytosis, then diffuse into interstitial fluid, then diffuse into blood
55
How do Thyroid Hormones Regulate oxygen use by?
by all cells during cellular respiration
56
How do Thyroid Hormones Increase basal metabolic rate (BMR) by?
by increasing production of ATP from carbohydrates and fats
57
Where do thyroid hormones Increase synergistic effects of epinephrine and norepinephrine?
in breakdown of glycogen and fat for energy production
58
What do thyroid hormones Stimulate production of?
of growth hormone, especially important during fetal development
59
Why do thyroid hormones Increase heart rate, breathing rate, and cardiac output?
so that more oxygen can be delivered to cells
60
What does TSH increase and stimulate?
increases thyroid hormone production and stimulates thyroid gland to grow (hypertrophy)
61
What is goiter?
enlarged thyroid gland
62
What is Grave’s disease?
autoimmune disease, Antibodies bind to receptors on thyroid and constantly stimulate production and secretion of thyroid hormones – goiter occurs
63
When does Hashimoto’s disease occur?
occurs when immune system attacks thyroid; therefore T3 and T4 are decreased
64
What is hyperthyroidism?
Excessive thyroid hormones
65
How is T3 compared to T4?
T3 is more active form, and much of T4 is converted into T3
66
What are symptoms of Hypothyroidism?
Weight gain, cold, depression, fatigue, possibly hair loss, dry skin, decreased ability to concentrate
67
What are symptoms of Hyperthyroidism?
Increased heart rate, breathing rate, anxiety, insomnia, weight loss, increased appetite, heat intolerance
68
What does Thyroid hormones increase when Hyperthyroidism?
increase effect of catecholamines
69
What hormones increase plasma calcium concentration?
parathyroid hormone, vitamin D
70
What does Calcitonin decrease?
blood calcium levels
71
Where is calcitonin secreted by?
parafollicular cells of thyroid gland
72
How does calcitonin decrease plasma calcium concentration?
by inhibiting osteoclasts
73
What is secretion of calcitonin stimulated by?
by high plasma calcium concentration, and it is only factor when concentration is very high
74
Where is Parathyroid hormone (PTH) secreted by?
secreted by parathyroid glands (four glands located in neck on thyroid gland)
75
What is PTH critically important to?
regulation of calcium levels
76
What type of conditions are for Rickets (in children) and osteomalacia (in adults)?
conditions for mineralization of bone matrix is deficient, causing bones to be soft and
easily fractured
77
What is major cause of rickets and osteomalacia?
deficiency of
vitamin D
78
What is Osteoporosis?
imbalance between bone resorption and bone formation, which results in decreases in bone mass and strength and leads to increased incidence of fractures
79
Where can osteoporosis occur in?
in people who are immobilized, and elderly, particularly females during menopause because of decreased estrogen
80
How can you prevent osteoporosis?
from calcium from diet, vitamin D, exercise, decrease stress (cortisol)
81
What does CRH from hypothalamus stimulate?
stimulates anterior pituitary to secrete ACTH, which acts on adrenal cortex to produce
cortisol (glucocorticoid)
82
Are all adrenal gland hormones steroids?
Yes
83
What is main function of Aldosterone, which is mineralocorticoid?
its main function is to regulate blood ion levels by signalling kidney to reabsorb sodium and excrete potassium and H+
84
When is Aldosterone produced?
when blood pressure is low
85
What does Cortisol , which is glucocorticoid increase?
increases blood glucose levels during stress
86
What are functions of DHEA, and how are they similar to testosterone?
DHEA is androgen and has functions similar to testosterone
87
Is it female or male that DHEA play more part?
it plays more significant role in adult females than males.** also made in gonads and brain**
88
What does DHEA permit and increase?
Permits action of epinephrine and norepinephrine on muscles, blood vessels, and
adipose tissue – increases breakdown of stored nutrients, vasoconstriction to maintain blood pressure
89
What does DHEA maintain?
Maintains cellular concentrations of metabolic enzymes required to produce glucose between meals – maintains blood sugar while fasting
90
What does DHEA decrease?
Decreases inflammatory response, such as capillary permeability and production of prostaglandins, often used as anti-inflammatory medication
91
What does DHEA prevent?
Prevents lysosome breakdown during tissue injury so that digestive enzymes don’t damage cells, also decreases capillary permeability during inflammation
92
What is DHEA important for?
Important for fetal development – differentiation of tissues
93
How endocrine system respond to stresses on body such as trauma, infection, pain, sleep deprivation, decreased oxygen, fright, excessive exercise
by increasing release of cortisol from adrenal cortex and epinephrine from adrenal medulla
94
What does CRH from hypothalamus stimulate?
stimulates anterior pituitary to secrete ACTH, which acts on adrenal cortex to produce cortisol (glucocorticoid)
95
What is Cortisol secretion highly linked to?
circadian rhythm
96
When is Cortisol secretion highest?
Secretion is highest first thing in morning and is lowest at night while sleeping
97
What is In Cushing’s syndrome?
there is excess cortisol in blood, even in non-stressed individual
98
What would be cause of cushing's syndrome?
may be primary defect (e.g., a cortisol-secreting tumour of adrenal gland) or may be secondary (usually due to an ACTH- secreting tumour of pituitary gland)
99
What does increased blood levels of cortisol in cushing's syndrome tend to promote?
tend to promote uncontrolled catabolism of bone, muscle, skin, and other organs
100
What are Problems associated with Cushing’s syndrome?
* Osteoporosis
* Muscles weakness
* Blood sugar increase to levels observed in diabetes mellitus
* Immunosuppression
* Redistribution of fat from limbs to trunk (buffalo hump and moon face)
* Hypertension (high blood pressure) – cortisol potentiates the effects of epinephrine
101
What are treatments for Cushing's syndrome?
Surgical removal of pituitary tumour, Adrenalectomy
102
What is cause of Addison's Disease?
Too little CORTISOL
* Hypoglycemia ( BS)
* Hypotension ( BP)
* Hyponatremia (low Na+)
103
What are Symptons of Addison's Disease?
* Convlusions
* Salt cravings
* Mood changes
* Headaches
* GI disturbances
* hyperpigmentation
104
What is Type 1 diabetes?
autoimmune disease where immune cells attack pancreatic beta islet cells that produce insulin, so no insulin can be produced
105
What does eating sugar lead to?
Eating sugar leads to insulin secretion from pancreas
106
What happens to Insulin receptors on body cells when you get type 2 diabetes?
They are down-regulated and do not respond to insulin (hyporesponsive)
107
What happens next when Sugar stays in bloodstream and doesn’t enter cells?
Cells are essentially starving because nutrients in blood are not going into cells
108
What are symptoms of type 2 diabetes?
increased hunger, high blood sugar, weakness, fatigue, dizziness/fainting
109
What is Healthy fasting BS range?
4-7 mmol/L
110
Where are small amount of estrogen and small amount of testosterone made in?
small amount of estrogen is made in testes, and small amount of testosterone is made in ovaries
111
What is Corpus luteum?
cells surrounding ovulated egg
112
What does corpus luteum produce?
It produces progesterone during few days after ovulation; if fertilization takes place, progesterone continues to be made
113
When does Estrogen production decrease?
when women enter menopause and ovaries stop developing egg follicles
114
Why do elderly people tend to sleep less?
Because Melatonin decreases as they age
115
What happens when GH and Thyroid hormone decrease?
less stimulating some production for maintaining muscle and bone density & Thyroid hormone production decreases that can lead to slower basal metabolism
