Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

INTS > INTS11 - Hypothalamic Pituitary Axes > Flashcards

INTS11 - Hypothalamic Pituitary Axes Flashcards

1
Q

Define endocrine gland

A

Group of cells which secrete messenger molecules in form of hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define a hormone

A

Bioactive messenger molecules secreted by endocrine glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define the endocrine system

A

Consist of the endocrine glands and the hormones they secrete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the differences in chemical messengers between the endocrine and nervous systems

A

Endocrine - hormones in blood circulation

Nervous - neurotransmitters released at synapses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the differences between the actions of signals in endocrine and nervous systems

A

Endocrine - signal acts on many cells

Nervous - signal acts on innervated neurons only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the differences between the speed of effect and length of duration between endocrine and nervous system

A

Endocrine - can take longer and exist over long periods

Nervous - quick effects with short periods of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Name some types of differences between endocrine and nervous systems

A

Type of chemical messengers
Number of cells the signal acts on
Time taken for action
Duration of signal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the location of the hypothalamus

A

Base of the Brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which pituitary gland is connected directly to the hypothalamus

A

Posterior pituitary lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is the anterior pituitary lobe and the hypothalamus connected

A

By short blood vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define location and general overview of thyroid gland

A

Located in the neck and regulates metabolism and growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the parathyroid glands and how are they structurally related to the thyroid gland

A

Glands located at posterior surface of thyroid glands, involved in calcium metabolism and regulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Give role and location of adrenal glands

A

Located at top of kidneys. Involved in release of glucocorticoids for stress responses e.g. adrenaline and epinephrine and release of mineralocorticoids for regulation of salt and water balance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give location and role of pancreas

A

Located at posterior of the stomach. Involved in regulation of blood glucose concentration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the two types of gonads, which system are they part of and what do they do.

A

Testes and ovaries.
Reproductive system.
Release of sex steroids/hormones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where is the kidney located and what is it’s roles

A

Located at posterior of middle of trunk.

Involved in the regulation of blood pressure, water reabsorption and calcium regulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Discuss the role of the heart as an endocrine organ.

A

Heart is not an endocrine organ but has endocrine function. Releases natriuretic peptides which have varying physiological effects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are natriuretic peptides

A

Hormones secreted by the heart into blood circulation involved in regulation of sodium excretion in kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is role and location of the thymus gland.

A

Location - upper anterior of trunk behind the sternum.

Releases thymus in to regulate immune function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Discuss endocrine role of gastrointestinal tract.

A

Contains endocrine cells but is not considered an endocrine organ. Hormones involved in digestion etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Discuss the endocrine role of adipose tissue

A

Releases hormones known as adipokines (also releases cytokines) that give information on fat stores and regulation of appetite.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which cell organelles would be present in high numbers in endocrine cells and why

A

Mitochondria - endocrine cells have high metabolism so require ATP
Rough ER- protein synthesis which makes up most of the hormones.
Secretory granules - storage of hormones until stimulus signalling their release is required.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which feature of the circulatory system is located near the endocrine cells

A

Blood capillaries. Allows hormones released from cells to be directly entered into circulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Discuss what neurosecretory cells are and how they function.

A

Neurons with typical neuronal morphology but can also release hormones which are stored in secretory vesicles at the axon terminal. Hormones released into circulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the three ways in which hormones act.

A

Endocrine.
Paracrine
Autocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Discuss endocrine mechanism of action of hormones.

A

Hormones act on target cells at a distance away from the releasing cell. Travel via the circulatory system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Discuss paracrine mechanism of action of hormones.

A

Hormones act on nearby target cells within the immediate area of release.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Discuss autocrine mechanism of action of hormones.

A

Hormones act on same cell from which they are released.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Give example of endocrine hormonal mechanism of action.

A

Insulin released from pancreatic beta cells promoting glycogenesis in the liver.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Give example of paracrine hormonal mechanism of action.

A

Histamines released from mast cells resulting in localised inflammation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Give example of autocrine hormonal mechanism of action.

A

Cytokine interleukin 1 released from monocytes which activates receptors on the surface of the same cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the three chemical structures of hormones.

A

Protein hormones
Steroid hormones
Amino acid derived hormones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Discuss features of peptide hormones

A

Water soluble. Can travel in circulation without carrier proteins as they are hydrophilic so cannot enter through plasma membranes. Act on cell surface receptors to trigger an intracellular signalling pathway.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Discuss features of steroid hormones.

A

Synthesised from cholesterol in the mitochondria when needed as it cannot be stored. Lipid soluble so can enter plasma membrane and act on intracellular receptors. Travel in circulation bound to carrier proteins due to hydrophobicity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Give examples of types of steroid hormones. Give example for each type.

A 
Glucocorticoid- cortisol 
Mineralocorticoids - aldosterone
Androgens - testosterone 
Oestrogen - estradiol 
Progesterone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Discuss features of amino acid derived hormones.

A

Derived from tyrosine, tryptophan or glutamic acid. Can be stored and are either lipid or water soluble, therefore can act on cell surface receptors or intracellular receptors. Travel in circulation with or without carrier proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Give examples of amino acid derived hormones .

A 
Thyroid hormones e.g. thyroxine T4 or tiiiodothyronine T3 
Catecholamines e.g. epinephrine 
Serotonin
Melatonin 
Histamines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Give examples of cell surface receptors and which types of hormones can bind to them.

A

All protein hormones and some amino acid derived hormones.

G protein coupled recpteors, tyrosine kinase receptors, voltage gated ion channels

39
Q

Give example of intracellular receptor and what type of hormone can bind to it.

A

Nuclear receptors. Steroid hormones and some amino acid derived hormones.

40
Q

What is the limbic system

A

A set of brain structures involved in controlling learning, emotion and behaviour.

41
Q

Give examples of homeostatic processes regulated by the hypothalamus

A

Water balance. Blood glucose concentration. Stress response. Food intake.

42
Q

What types of proteins are hypothalamus releasing factor hormones

A

Protein hormones

43
Q

Does the hypothalamus receive neuronal input from other brain regions. If so, which is the main region.

A

Yes. Brain stem.

44
Q

Give other name for the pituitary as a whole.

A

Hypophysis.

45
Q

Give other name for anterior pituitary.

A

Adenohypophysis.

46
Q

Give other name for posterior pituitary, and why it is so called.

A

Neurohypophysis. Neural in origin and develops as an extension of the hypothalamus neurons.

47
Q

What functions are regulated by the anterior pituitary lobe.

A

Growth. Metabolic rate. Sex cell maturation. Stress responses. Blood glucose concentration regulation.

48
Q

What functions are regulated by the posterior pituitary lobe.

A

Water balance in kidney. Uterine contraction. Breast function.

49
Q

What are the two types of specialised neurosecretory cells.

A

Parvocellular and magnocellular.

50
Q

What is the stalk between the hypothalamus and the posterior or anterior pituitary lobe.

A

Infundibulum

51
Q

What are the two major hormones released by the posterior pituitary.

A

Vasopressin (anti-diuretic hormone)

Oxytocin

52
Q

What are the major hormones released by the anterior pituitary

A

LH, FSH, TSH, PRL, GH, ACTH

53
Q

Discuss the structural relationship between the hypothalamus and the anterior pituitary lobe.

A

Cell bodies in the hypothalamus extend to the base of the hypothalamus forming the median eminence. Blood vessels form the capillary plexus which provides blood supply to the neurocrines. Portal circulatory system exists between capillary plexus and anterior pituitary, bathing the lobe with circulation.

54
Q

Describe the structural relationship between the hypothalamus and the posterior pituitary.

A

Cell bodies in the hypothalamus have axons which stretch down to form the posterior pituitary. Hormones synthesised in the cell bodies, travel down the axon and are stored in nerve terminals.

55
Q

Define neurosecretion.

A

Secretion of hormones from the neuron.

56
Q

Give examples of various hypothalamo-pituitary axes and what they regulate.

A

Hypothalamo-pituitary-gonadal axis regulates reproductive function
Hypothalamo-pituitary-adrenal axis regulates stress responses

57
Q

Where are parvoecllular neurosecretory cell bodies located and what do they do

A

Located in hypothalamus in the paraventricular nucleus. Have short axons forming the median eminence at the base of the hypothalamus. Neuronal terminals secrete hypothalamic hormones into the primary capillary plexus. Long portal veins carry the hormones to the secondary capillary plexus. Hormones bathe the anterior pituitary lobe.

58
Q

Where are magnocellular neurosecretory cell bodies located and what do they do

A

Located in the hypothalamus in paraventricular supraoptic nuclei. Contain Long axons which pass through the median eminence and form the posterior pituitary. Neurons secrete hormones into general circulation.

59
Q

What are the five types of cells in the anterior pituitary lobe and what hormones do they release.

A 
Somatotroph 
Thyrotroph
Lactotroph
Gonadotroph 
Corticotroph
60
Q

Give the five hypothalamic releasing hormones, released into the anterior pituitary lobe, and their respective antihero our pituitary hormones released into circulation.

A

Prolactin releasing hormone. PRH. Prolactin.
gonadotropin releasing hormone GnRH. Follicle stimulating hormone FSH and luteinising hormone LH.
Growth hormone releasing hormone GHRH. Growth hormone. Somatotropin.
Corticotropin releasing hormone CRH. Adrenocorticotropic hormone. ACTH.
Thyrotropin releasing hormone TRH. Thyroid stimulating hormone.

61
Q

Give the six anterior primary hormones and their target tissues.

A

Growth hormone - liver, muscle, bone.
Thyroid stimulating hormone - thyroid gland.
Prolactin- mammary glands in breast.
Luteinising hormone - Gonads.
Follicle stimulating hormone - gonads.
Adrenocorticotropic hormone - adrenal cortex

62
Q

When is ADH released from the pituitary and what is its effect.

A

Released from posterior pituiatary in response to high blood osmolarity - high salt/ions in blood. Occurs due to dehydration or a salty meal. Constricts blood vessels and increases reabsorption of water into blood.

63
Q

What is the effect of oxytocin on its target tissue, and what is its feedback loop.

A

Acts on uterus to cause uterine contractions, on a positive feedback loop.

64
Q

What is the effect of prolactin on its target tissue.

A

Prolactin acts on mammary glands in the breast and promotes the production of milk.

65
Q

What is the effect of FSH on its target tissue.

A

Ovary - promotes follicular growth. Release of oestrogen. Stimulates sex cell maturation.
Testes - sex cell maturation.

66
Q

What is the effect of LH on its target tissue.

A

Ovary - triggers ovulation. Stimulates production of oestrogen and progesterone.
Testes - stimulates testosterone production

67
Q

What is the effect of growth hormone on its target tissue.

A

In muscle, tissue and liver. Growth hormones stimulates breakdown of adipose fuelling growth. Stimulates breakdown of glycogen into glucose so increased metabolism leading to increased growth. Enhances cell proliferation.

68
Q

What is the effect of ACTH on its target tissue.

A

Adrenocorticotropic hormone induces production of glucocorticoids which regulate stress responses.

69
Q

What is the effect of TSH on its target tissue.

A

Thyroid stimulating hormone release thyroid hormones e.g. triiodothyronine T3 and thyroxine T4 to aid the regulation of metabolism. Works in a negative feedback loop.

70
Q

Discuss the effects on the female reproductive system as an endocrine organ.

A

FSH stimulates development of ovarian follicles. Androgens converted to oestrogen by granulosa cells.

71
Q

Discuss the effects on the male reproductive system as an endocrine organ.

A

LH acts on leydig cells promoting testosterone release. FSH Stimulates Sertoli cells in testes promoting spermatogenesis.

72
Q

Discuss the effects on the thyroid and parathyroid glands as an endocrine organ.

A

Release of T3 and T4 to regulate metabolism. Release of PTH to regulate Ca2+ metabolism.

73
Q

What type of cells releases which posterior pituitary hormones.

A

Magnocellular neuronal cell bodies release vasopressin and oxytocin.

74
Q

When is vasopressin release stimulated.

A

High blood electrolyte concentration. Urine is usually detected as concentrated in order to preserve blood electrolyte concentration within healthy limits.

75
Q

What effect does oxytocin have on breast cells.

A

Oxytocin leads to contraction of myoepithelial cells in breasts which cause the ejection of milk during breast feeding.

76
Q

What are the two effects of oxytocin.

A

Uterine contractions. Milk ejection in breast.

77
Q

What are the two mechanisms of endocrine dysfunction.

A

Hypersecretion - too much hormone secreted

Hyposecretion - too little hormone secreted.

78
Q

What are the effects of hypersecretion of vasopressin, including medical condition.

A

Hyponatremia - low sodium concentration in blood leading to swelling in cells due to increased blood volume.

79
Q

What are the effects of hyposecretion of vasopressin including medical condition.

A

Diabetes insipidus - large volumes of unconcentrated urine produced resulting in dehydration.

80
Q

What are the effects of hypersecretion of glucocorticoids and give example of glucocorticoid. Include medical condition.

A

Cortisol. Cushing’s syndrome leading to fat redistribution and muscle weakness. Also results in thin skin leading to bruising.

81
Q

What are the effects of hyposecretion of glucocorticoids.

A

Muscle weakness, weight loss, fatigue.

82
Q

What are the effects of hypersecretion of thyroid hormones.

A

Hyperthyroidism results in high metabolic rate, high heart rate, weight loss, intolerance to heat.

83
Q

What are the effects of hyposecretion of thyroid hormones.

A

Hypothyroidism - low metabolic rate so weight gain likely. Reflexes can be slow. Cold intolerance.

84
Q

What is cretinism and how does it occur.

A

Hypothyroidism in infants as a result of maternal hypothyroidism.

85
Q

What are the effects of hypersecretion of androgens. Give example of androgen.

A

Testosterone.
Women - reproductive dysfunction. Increased follicular growth.
Men - behavioural changes.

86
Q

What are the effects of hyposecretion of androgens. Give example of androgen.

A

Testosterone.

Man - loss of libido. Infertility.

87
Q

What are the effects of hypersecretion of oestrogen.

A

Females - menstrual irregularities. Uterus enlargement.

Males - feminisation. Loss of libido.

88
Q

What are the effects of hyposecretion of oestrogen.

A

Females - lowered libido. Reduced bone density.

89
Q

What are the effects of hypersecretion of growth hormone.

A

Protrusion in growths e.g. on jaw. Soft tissue formation. Acromegaly in adults - increased bone growth.

90
Q

What are the effects of hyposecretion of growth hormone.

A

Childhood - growth failure.

Adulthood - increased body fat and decreased muscle.

91
Q

What are the effects of hypersecretion of prolactin.

A

Hyperprolactinemia - unexpected lactation. Disrupted menstrual cycle. Results in loss of libido in females.

92
Q

What are the effects of hyposecretion of prolactin.

A

Ovarian dysfunction and lack of milk lactation. Can also cause sexual dysfunction in males.

93
Q

Why is it difficult to accurately measure hormone levels in circulation.

A

Hormone levels continuously change as a result of different simulation, so cannot be measured accurately so requires dynamic testing.

94
Q

How are hormone levels measured.

A

Utilisation of antibodies which detect the hormone and are coupled to a reporting system e.g. chemical colour change so can be quantified.

INTS (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions