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Flashcards in Endocrine Physiology Deck (135)
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1
Q

What causes dwarfism in most of the cases?

A

Panhypopituitarism where there is undersecretion of all ant pituitary hormones

2
Q

In what percentage of dwarfs is there undersecretion of growth hormone alone?

A

33.3% (1/3)

The dwarf still matured sexually and is able to reproduce

3
Q

What’s the cause of dwarfism in the LeviLorain dwarf?

A

The LeviLorain dwarf is able to produce growth hormone but there is an hereditary inability to form somatomedin C(a hormone produced by the liver that promotes the action of growth hormone)

4
Q

What disease is associated with over secretion of growth hormone in childhood?

A

Hyperglycemia due to oversecretion of GH, which antagonises the action of insulin leading to degeneration of beta cells
In 10% of giants, it leads to full blown diabetes

5
Q

Inability to produce growth hormone in adult hood can lead to ……

A

Increased rate of aging due to decreased protein deposition in most tissues of the body and replacement with fat

6
Q

What percentage of secretory cells do the gonadotrophs make up?

A

20%

7
Q

What is the name of the secretory cells of the testes?

A

Leydig cells that secrete testosterone

8
Q

What cells help to support sperm cell maturation?

A

Sertoli cells

9
Q

How many amino acid residues does thyroglobulin have and what is its molecular weight?

A

140

660000

10
Q

What’s the minimum daily intake of iodine I order to avoid diseased state of thyroid gland?

A

100-150mg

11
Q

What percentage of iodide is used by the body?

A

1/3 is used by thyroid gland

2/3 is excreted

12
Q

What stimulates the endocytosis of organified thyroglobulin back into the cell?

A

TSH

13
Q

Propylthiouracil helps to prevent …….. by inhibiting ………..

A

Hyper thyroidism

Thyroperoxidase

14
Q

Concerning transportation of thyroid hormones, state the percentage of how they are transported?

A

67% by tyrosine binding globulin
20% by tyrosine binding prealbumin
13% by albumin

15
Q

In what form is thyroid hormone physiologically active?

A

In free form(same as Ca)

16
Q

What are the daily amounts of thyroid hormone secreted?

A

80mg T4
4 mg T3
2mg rT3

17
Q

What is the effect of Stress on TSH?

A

Decreases TSH levels

Glucocorticoids inhibit the secretion of TRH

18
Q

What’s the effect of low thyroid hormones in men and women?

A

Low libido in men

Frequent menstrual bleeding in women and irregular periods

19
Q

What’s the effect of high levels of thyroid hormones in men and women?

A

Impotence in men

Reduced menstrual bleeding and amenorrhea

20
Q

What are the main functions of aldosterone?

A

Na reabsorption

K and H secretion

21
Q

What steroidal hormone antagonizes vitd3

A

Cortisol

22
Q

NE causes vasoconstriction via ….. while epinephrine causes vasodilation via ….

A

Alpha receptors

Beta 2 receptors

23
Q

What’s the action of catecholamines on K conc?

A

Initial rise in K, prolonged fall in K because it’s entry into the cell is increased

24
Q

Deficiency of 21 beta hydroxylase leads to what?

A

Undersecretion of cortisol and aldosterone with oversecretion of androgens leading to adrenogenital syndrome or congenital adrenal hyperplasia

25
Q

Deficiency of 17 alpha hydroxylase leads to what symptoms?

A

Inability to produce androgens and cortisol but excessive amounts of aldosterone is produced

26
Q

What are the physiologic effects of dopamine?

A

Increased renal blood flow
+ve ionotropic effect on the heart
Increased systolic bp, but doesn’t affect diastolic BP?

27
Q

What are the stimulus for the release of adrenal medulla hormones?

A

Sym Ns

Hypoglycemia

28
Q

What’s the length of the pineal gland?

A

10mm

29
Q

What are the examples of sulfonylurea drug?

A

Tolbutamide, glyburide

30
Q

What’s the function of metformin?

A

It’s a biguanide drug which up regulate insulin receptors on target tissues. It helps to treat lifestyle diabetes

31
Q

What hormone is regarded as the hormone of Abundance?

A

Insulin

32
Q

What hormone is regarded as the hormone of starvation?

A

Glucagon

33
Q

Beta adrenergic …… levels while alpha adrenergic agents ………

A

Increases cAMP

Decreases cAMP

34
Q

What are the stimulators factors for the release of somatostatin?

A

Nutrients
Glucagon
Beta adrenergic agonists

35
Q

Somatostatin is inhibited by what hormone and inhibits what hormones?

A

Insulin

Insulin and Glucagon

36
Q

What quantity of Calcium is ingested per day?

A

1000mg
Only about 1/3 is absorbed from GIT into ECF

About 190mg is lost back to the gut

37
Q

What is chvostek sign indicate?

A

The Chvostek sign is a clinical finding associated with hypocalcemia, or low levels of calcium in the blood. This clinical sign refers to a twitch of the facial muscles that occurs when gently tapping an individual’s cheek, in front of the ear.

38
Q

Constipation, polyuria and dipsia , lethargy and hyporeflexia are usually symptoms seen in

A

Hypercalcemia

39
Q

Hypocalcemia is characterized by what symptoms?

A

Hyperreflexia
Muscle cramps
Spontaneous twitching
Tingling and numbness

40
Q

Trousseau sign indicates ………

A

Hypocalcemia

It is indicated by carpopedal spasms

41
Q

How many amino acids does PTH have?

A

84 aa, secreted by chief cells

Biological activity is on N terminal 34 amino acid

42
Q

In what part of the kidney is calcium reabsorbed under the influence of PTH?

A

Distal tubule

43
Q

PTH action on the kidney, what happens?

A

Promotes PO4 secretion at PCT and Ca reabsorption at DCT

44
Q

Secondary hyperparathyroidism is usually caused by

A

Vit D deficiency or chronic renal failure

There are high levels of PTH in the blood, but blood levels of Ca are low or normal, but never high

45
Q

What’s the treatment for hypoparathyroidism?

A

Ca supplements

And supplements of active vit d3

46
Q

Albright’s hereditary osteodystrophy is characterized by

A

Pseudohypoparathyroidism (PHP) is a genetic disorder in which the body fails to respond to parathyroid hormone.

47
Q

Furosemide is used to treat ……..

A

Hypercalcemia by inhibiting Ca reabsorption

48
Q

Etidronate is used to treat ……

A

Hypercalcemia by inhibiting bone resorption

49
Q

How many amino acids does Calcitonin have?

A

32

50
Q

What is the effect of cortisol on ca metab?

A

Decreases serum ca

Antagonises Vit d3 so it prevents absorption of ca and PO4 from the gut

51
Q

…. Increases renal Ca excretion and increases absorption of Ca from the gut. Net effect is +ve

A

Growth hormone

52
Q

How many amino acids does Renin have?

A

340aa

53
Q

What are sufonylurea drugs?

A

Sulphonylureas are a class of oral (tablet) medications that control blood sugar levels in patients with type 2 diabetes by stimulating the production of insulin in the pancreas and increasing the effectiveness of insulin in the body.

54
Q

Angiotensin II has how many aa?

A

8 aa

It is an octapeptide

55
Q

AG II decreases GFR by……

A

Constriction of efferent arterioles and constriction of mesangial cells to reduce the surface area of the glomerular capillaries

56
Q

AG directly increases plasma osmolality by……

A

Directly increasing the reabsorption of Na at the PCT

57
Q

How does AG II indirectly increase BP?

A

It stimulates sympathetic fibres to release NE which causes vasoconstriction via alpha receptors

58
Q

What’s the half life of angiotensin II?

A

1-2 mins

59
Q

What’s the dimension of the testes?

A

2.5*4cm

60
Q

What are the substances produced by sertolli cells?

A

Inhibin
Activin
Androgen binding proteins
Mullerian inhibiting hormone

61
Q

How are sex hormones transported in the blood?

A
  1. Sex hormone binding globulin or gonadal steroid binding globulin 65%
  2. Albumin 33%
  3. Cortisol binding globulin to a little extent
62
Q

What’s the action of cAMP on cholesterol?

A

Increases its conversion to pregnenolone by activating pkA

63
Q

What are the characteristics of hypogonadism in childhood in males

A

Tallness due to late epiphyseal plate closure
Small genitalia
High pitched voice
Narrow shoulders and small muscles
Sparse body hair
Sterility due to the absence of spermatogenesis
Pubic hair with female pattern

64
Q

Sterility in males may be due to ……

A

Little or no testosterone to stimulate spermatogenesis

65
Q

What structure secretes relaxin?

A

Corpus luteum

66
Q

What hormone increases basal body temp in females?

A

Progesterone

67
Q

What maintains the corpus luteum and where is it produced from?

A

HCG

Syncytiotrophoblast and placenta later on

68
Q

When does the mammary gland along with its lobules and ducts develop?

A

Halfway through pregnancy

69
Q

The largest duct of the mammary gland is the …..

A

Lactiferous duct which drain into sinuses before coming out into the areola

70
Q

Around what month is oogenesis completed in fetal life?

A

7 month

71
Q

What secretes inhibin in females?

A

Granulosa cells

72
Q

What hormone increases uterine sensitivity to oxytocin and increases uterine excitability?

A

Estrogen

It also increases uterine blood flow

73
Q

What hormone acts as an antagonist to estrogen by decreasing the number of estrogen receptors and decreasing uterine excitability and sensitivity?

A

Progesterone

74
Q

….. stimulates the enlargement of the lobules and alveoli of the breast?

A

Progesterone

75
Q

At what day does the dominant follicle emerge?

A

Day 6

76
Q

What is responsible for ovulation?

A

LH surge

77
Q

Apart from the LH surge, how is the follicle ruptured?

A

Through the action of proteolytic enzymes
Progesterone
Prostaglandins

78
Q

At what day does the corpus luteum degenerate of pregnancy doesn’t occur?

A

Around day 24

79
Q

In the follicular phase, estrogen inhibits ……. And enhances …….

A

FSH

LH

80
Q

What hormone inhibits LH?

A

Progesterone

81
Q

In the proliferative phase, occurs from days ………. And what hormone influences this?

A

5-14

Estrogen that causes endometrial thickening

82
Q

In the secretory phase, occurs from days ………. And what hormones influences this?

A

14-28
Progesterone causes the endometrium to be secretory
Estrogen causes endometrial vascularisation

83
Q

Polymenorrhea is characterized by?

A

A menstrual cycle that’s shorter than 21 days caused by stress and endometriosis

84
Q

Dysmenorrhea is characterized by ……..

A

Painful menstruation and menstrual cramps

85
Q

What is menometrorrhagia?

A

Menometrorrhagia, defined as excessive and prolonged uterine bleeding occurring at irregular and/or frequent intervals, occurs in up to 24% of women aged 40-50 years.

86
Q

The syncytiotrophoblast is formed ———— after fertilization?

A

3-6 days

87
Q

The placenta is formed when?

A

7-8 weeks after pregnancy

88
Q

At what week is hCG maximum during pregnancy?

A

10-12 weeks

89
Q

…… is also known as human chorionic somatomammotropin?

A

Human placental lactogen

90
Q

What hormone produced by the placenta promotes genital tract differentiation and fetal testicular secretion?

A

hCG

91
Q

What hormone during pregnancy acts as an insulin antagonist, decreases glucose utilization by the mother and causes Na, K and Ca retention?

A

Human chorionic somatomammotropin

92
Q

The breast ductal system dev is stimulated by …….

A

Estrogen

93
Q

What hormone increases maternal ventilation during pregnancy?

A

Progesterone

94
Q

In how many weeks can hCG be detected in the urine

A

About 2 weeks

14 days

95
Q

By how many percent does CO increase in a 20 week pregnant woman?

A

30-40%

96
Q

In pregnancy, blood volume and respiratory volume are increased by …….. but BMR is increased by ……

A

20%

15%

97
Q

Polymenorrhea is characterized by

A

A cycle shorter than 21 days due to stress and endometriosis

98
Q

At what week does labor start?

A

At week 40

99
Q

Braxton Hick’s contractions are …….

A

Rhythmic contractions of the myometrium

100
Q

How long do the stages of labor last?

A

1st stage- 8-24 hours
2nd stage 20-90 mins
3rd stage 15-30 mins

101
Q

The shedding of the endometrium after birthing is a discharge called

A

Lochia

102
Q

At what stage of pregnancy is the baby given birth to

A

2nd stage

103
Q

What two hormones contribute to the functional dev of the breast by stimulating the production of the enzymes?

A

Prolactin and hCG

104
Q

Rhythmic method of contraception involves ————-

A

Avoid fertile period + or - 3 days around ovulation

105
Q

In how many weeks is the pre pregnant body regained after birthing?

A

4-6 weeks

106
Q

Cholostrum contains …… and …… that helps to provide immunity to the child

A

Lactoferrin which has anti bacterial action and IgA

107
Q

High levels of prolactin can inhibit …… and ………

A

Estrogen and progesterone and this can disrupt the menstrual cycle and lead to infertily. That’s why lactation during breastfeeding when there is high levels of prolactin, can be used as a form of natural contraceptive

108
Q

What’s the half life of insulin?

A

5-6 mins

109
Q

What stimulates the secretion of insulin?

A

Blood sugar levels 90mg/dL

110
Q

Congenital absence of 1 alpha hydroxylase leads to

A

Vit D resistance

111
Q

In what type of diabetes mellitus is there weight loss?

A

Type 1

112
Q

What hormones are used as steroidal contraceptives?

A

Estrogen and Progesterone

Or progesterone alone

113
Q

What are the symptoms of deficiency of 17 alpha hydroxylase?

A

Lack of pubic and axillary hair in females
Deficiency of glucocorticoids
High levels of mineralocorticoids

114
Q

In Depot intramuscular injection contraception, how long does it last?

A

2-3 months

115
Q

How long can a subdermal contraceptive last?

A

< 2 years

116
Q

Exogenous testosterone supports …….. but does not support …..

A

Androgen effects of sexual function and other targets of testosterone but does not support spermatogenesis

117
Q

In menopause, the existing follicles are unresponsive to …….

A

FSH and LH

118
Q

What are the characteristics of hotflushes?

A
Vasomotor instability
Wide fluctuation in BP
Fatigue
Nervousness
Emotional outburst
Insomnia 
Palpitations 
Vertigo
Headache and numbness
Osteoporosis
119
Q

What can be used to treat hot flushes?

A

Estrogen replacement therapy
Estrogen progesterone replacement therapy
Calcium supplements

120
Q

Addison’s disease is characterized by…..

A

Weight loss
Chronic hypotension(addisonian crisis)
Elevated levels of ACTH leading to hyperpigmentation
Hyperkalaemia

121
Q

What is the action of thyroid hormones on serum cholesterol?

A

It upregulates LDL receptors of the liver to transport cholesterol into the liver
Increases the uptake of cholesterol via steroid producing cells
Excretes sterol via the gut

122
Q

How does stress affect thyroid hormone synthesis?

A

Stress decreases tsh levels cause glucocorticoids inhibit TRH

123
Q

Whats the action of melatonin in humans?

A

it delays the onset of puberty by inhibiting the gonads

124
Q

AG1 has ………….. amino acids while AG2 has …………… aa

A

10

8

125
Q
in the dev of the gonads,
5th-6th week is for
7th-8th week is for
8th -12th week is for
10th-12th week is for
A
  1. dev of bipotential gonad
  2. sex determination and gonadal differentiation
  3. endocrine hormone secretion
  4. development of internal genitalia(testosterone and MIF dependent) and external genitalia(testosterone dependent only)
126
Q

how long does spermatogenesis take?

A

72-74 days

127
Q

GnRH is a peptide with how many aa?

A

10

128
Q

what is the normal sperm count?

A

100-200million per ml

amount of sperm in a single ejaculate is 3-4ml

129
Q

turner’s syndrome is … while kinefelter syndrome is ………

A

45X0

47XXY

130
Q

characteristics of turner syndrome includes ……….

A

shorter than average
slightly larger necks
infertility

131
Q

characteristics of turner syndrome includes ……….

A

shorter than average
slightly larger necks
infertility

132
Q

characteristics of Klinefelter syndrome includes ……….

A

low testosterone production
reduced fertility or infertility
taller than average
moree breast tissue

133
Q

granulosa cells secrete … while theca cells produce ………

A

inhibin and they also produce estradiol(under the action of FSH)
granulosa cells receive androstenedione made by the theca cells as their precursor for its synthesis
theca cells produce androstenedione from cholesterol under the action of LH

134
Q

…… is the life saving hormone

A

Aldosterone

135
Q

Estrogen has actions similar to what hormone? Cause it causes …….

A

Aldosterone

Salt and water retention