Homeostasis And The Endocrine System Flashcards

1
Q

What is homeostasis?

A

The existence of a stable environment

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

Name some conditions that must be controlled by the body

A

Body temperature
Water content
Carbon dioxide
Blood sugar
Blood pressure

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

What is homeostatic regulation?

A

The adjustment of physiological systems to preserve homeostasis

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

Name the 5 elements of a homeostatic control system

A

Stimulus
Receptor
Input
Output
Response

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

Which type of feedback is more common negative or positive?

A

Negative feedback

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

Name some negative feedback systems

A

Temperature control
PH
Blood sugar

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

Name some positive feedback systems

A

Haemostasis
Labour and delivery

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

What is the control centre for thermoregulation?

A

Hypothalamus

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

Name some heating mechanisms of the body

A

Shivering
Hairs on our body stand up
Response to get up and move

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

Name some cooling mechanisms in the body

A

Sweating
Redistribute the blood

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

What are the two main systems for homeostatic regulation?

A

Intrinsic and extrinsic

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

What is another name for intrinsic regulation?

A

Auto regulation

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

What is auto regulation?

A

It is when cells, tissues and organs adjust automatically to environmental changes

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

What is extrinsic regulation?

A

It results in either your nervous system making changes or your endocrine system

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

What can cause homeostasis to go wrong?

A

An infection, injury or a genetic abnormality

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

Who are most vulnerable to homeostatic disruption?

A

Newborns and elderly

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

Why are newborns vulnerable to homeostatic disruption?

A

Because of the immaturity of their systems such as immune system, renal function, endocrine system, thermoregulation

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

Why are elderly more vulnerable to homeostatic disruptions?

A

They are less responsive to hormones
Have decreased efficiency of the heart and circulatory system
Have loss of neurones and neurotransmitters (nervous system is slower)

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

What are the two types of glands?

A

Exocrine and endocrine

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

What do exocrine glands do?

A

They secret their products into ducts that empty out into a surface or cavity

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

What do endocrine glands do?

A

They secret hormones into intracellular spaces, then hormones diffuse into the bloodstream,

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

Do endocrine glands have ducts?

A

No

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

Name 3 systems that produce hormones that aren’t glands

A

Stomach
Small intestines
Kidney

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

What are the main functions of the endocrine system

A

They regulate sodium and water balance (blood volume)
They regulate calcium and phosphate balance (preserves extra cellular fluid concentration for cell survival )
They regulate energy balance and control of macronutrient utilisation and storage
Regulate responses to stress
Regulate reproduction, sexual development and growth

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

What are the 2 types of hormones?

A

Non-steroidal hormones
Steroidal hormones

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

Which category of hormone attaches to a surface receptor?

A

Non-steroidal hormone

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

What mechanism do non-steroidal hormones work by?

A

Second-messenger mechanism

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

What are non-steroidal hormones?

A

Whole proteins which are short chains of amino acids or could just be one amino acid

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

Which category of hormone can pass through the cell membrane of the target organ?

A

Steroidal hormones

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

What are steroidal hormones?

A

Small lipid soluble chemical

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

Which category of hormone normally has a slower action?

A

Steroidal hormones

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

Which category of hormone will produce a hormone-receptor complex?

A

Steroidal hormone

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

What are the two types of non-steroidal hormone?

A

Protein or peptide hormones
Amino acid derived hormones

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

Which type of non-steroidal hormone is more common?

A

Protein or peptide hormones

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

How are protein/peptide hormones synthesised?

A

They are synthesises as pre-prohormones in which they undergo transformation at the required time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Where are protein/peptide hormones stored?

A

They are stored in secretory glands

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

Give some examples of protein/peptide hormones

A

Insulin
Glucagon
Adrenocorticotropic hormone (ACTH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What are amino-acid derived hormones synthesised from?

A

Other amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Give some examples of amino-acid derived hormones

A

Adrenaline
Noradrenaline
Dopamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are steroidal hormones derived from?

A

Cholesterol

41
Q

Where are steroidal hormones synthesised?

A

Adrenal cortex
Gonads
Placenta

42
Q

Which type of hormone requires binding proteins in the blood?

A

Steroidal hormones

43
Q

Give some examples of steroidal hormones

A

Testosterone
Oestrogen
Progesterone

44
Q

What are the 5 major pathways to hormone effects?

A

Paracrine pathway
Autocrine pathway
Endocrine (telecines) pathway
Synaptic pathway
Neuroendocrine pathway

45
Q

What is the paracrine pathway?

A

It is where hormones are produced in a cell, secreted, act directly on nearby receptor cells

46
Q

What is the autocrine pathway?

A

It is where the hormone is secreted by the cell and then that cell has a receptor for itself -> the hormone that is releases acts on the cell that has produced it

47
Q

What is the endocrine pathway?

A

It is where hormone are produced in a cell, secreted and travel through blood vessels to distant cells, attach to receptors, act on the cell

48
Q

What is the synaptic pathway?

A

Hormones produced in neurone, secreted and travel along axon to the synapse where they are re released and taken up by nearby neurone with appropriate receptors to exert an effect

49
Q

What is the neuroendocrine pathway?

A

Hormones produced in neurone, secreted, travel along axon to synapse, released, take up into vascular system, travel to distant cells with appropriate receptors to exert an effect

50
Q

The hypothalamus contains neurones that synthesise inhibiting and releasing hormones to act on what?

A

The pituitary gland

51
Q

Name 4 common releasing hormones from the hypothalamus

A

Growth hormone RH
Thyrotropin RH
Corticotropin RH
Gonadotropin RH

52
Q

Name 4 mechanisms that trigger the hypothalamus or pituitary gland to initiate a hormone release

A

Neurotransmitters
Injury
Release of chemical mediators after injury
Neuroendocrine signals

53
Q

What are some of the causes of altered hormone function?

A

Impairment of the hypothalamus or pituitary gland
Impairment of the endocrine gland
Too much or too little hormone produced and secreted
Inactive hormone production by the gland
Inadequate hormone receptor binding
Lack of response by the target cell to the hormone
Impaired negative feedback loop
Hormone produced ectopically
Impaired hormone metabolism and elimination

54
Q

Name some disorders of the endocrine system

A

Acromegaly
Gigantism
Achondroplasia

Hyperthyroidism
Hypothyroidism
Cushing syndrome
Diabetes mellitus/diabetes insipidus
Pheochromacytoma
Glucagonoma
Somatostatinoma

55
Q

Where is the thyroid located ?

A

Anterior part of the neck

56
Q

What is the shape of the thyroid gland?

A

Butterfly shape

57
Q

What does the thyroid do?

A

Plays a critical role in stimulating metabolism

58
Q

What does the thyroid facilitate the breakdown of?

A

Carbohydrates, proteins, fats for energy, stimulating heat and glucose production

59
Q

What does the thyroid produce?

A

Structural proteins, enzymes and other hormones

60
Q

What does the thyroid promote?

A

Growth and development in children both mentally and physically

61
Q

What happens if thyroid hormone is released?

A

Increased glucose absorption
Release of lipid from adipose tissue
Metabolism of proteins from muscle tissue
Increased cholesterol breakdown in liver
Increased oxygen consumption
Increased body heat production
Increased cardiac output
Increased gastric motility
Increased muscle tone and reactivity
Increased activist action of cognitive processes

62
Q

What is hyperthyroidism?

A

Excessive thyroid hormone production

63
Q

What is hyperthyroidism caused by?

A

Increased stimulation of thyroid gland
Diseases of thyroid gland
Increased production of TSH by a pituitary tumour
Some medications containing high levels of iodine
Health food supplements containing seaweed

64
Q

What is hypothyroidism?

A

Deficient thyroid hormone
Can be congenital or acquired

65
Q

When does congenital hypothyroidism occur?

A

During foetal development

66
Q

What causes congenital hypothyroidism?

A

A lack of thyroid development -> lack of thyroid hormone syntheisis

67
Q

Wha does congenital hypothyroidism look like?

A

In uterus, maternal T4 crosses placenta so baby appears normal at birth
Results in developmental delay and impaired growth

68
Q

What can help congenital hypothyroidism?

A

Thyroid replacement therapy

69
Q

What is Grave’s disease?

A

Excessive stimulation of the thyroid gland, an autoimmune condition

70
Q

Which gender is Grave’s disease more common in?

A

Women

71
Q

Name some symptoms of Grave’s disease

A

Fine hair
Bulging eyeballs
Muscle wasting
Sweating
Tachycardia
Weight loss
Tremor

72
Q

What is acquired hypothyroidism caused by?

A

Due to autoimmune disorder, iodine deficiency, surgical removal or radiation therapy to thyroid gland, medications that destroy the thyroid gland and genetic defects

73
Q

Which sex is acquired hypothyroidism more common in?

A

Women

74
Q

Name some symptoms of acquired hypothyroidism

A

Course, brittle hair
Large tongue
Hoarseness
Constipation
Muscle wasting

75
Q

What is the treatment of acquired hypothyroidism?

A

Hormone replacement life long therapy

76
Q

What is the treatment for Grave’s disease?

A

Radiation treatment of thyroid
Some medications to prevent hormone production
Can have part or all of the thyroid removed

77
Q

What are 3 homeostatic regulation mechanisms?

A

Autoregulation
Nervous system
Endocrine

78
Q

What bodily activities is calcium essential to?

A

Muscle function
Nerve function
Heart function
Bone density

79
Q

What effect does calcitriol have on the skeletal system?

A

Promotes calcium and phosphate ion absorption along the digestive tract

80
Q

What effect does growth hormone have on the skeletal system>

A

Stimulates osteoblast activity and synthesis of bone matrix

81
Q

What effect does thyroxine have on the skeletal system?

A

With growth hormone, stimulates osteoblast activity and synthesis of bone matrix

82
Q

What effect do sex hormones have on skeletal system?

A

Stimulates osteoblast activity and the synthesis of bone matrix; oestrogen stimulate epiphyseal closure earlier than androgens

83
Q

What effect does parathyroid hormone have on skeletal system?

A

Stimulates osteoclast and osteoblast activity; elevates calcium ion concentration in body fluids

84
Q

What effect does calcitonin have on skeletal system?

A

Inhibits osteoclast activity; promotes calcium loss by kidneys; reduces calcium ion concentrations in body fluids

85
Q

What is the primary source of calcitriol?

A

Kidneys

86
Q

What is the primary source of growth hormone?

A

Pituitary gland

87
Q

What is the primary source of thyroxine?

A

Thyroid gland (follicle cells)

88
Q

What is the primary source of sex hormones?

A

Ovaries
Testes

89
Q

What is the primary source of calcitonin?

A

Thyroid gland

90
Q

What does low calcium plasma levels cause the parathyroid glands to secrete?

A

Parathyroid hormone (PTH)

91
Q

What are the 3 responses from PTH release?

A

Bone response -> osteoclasts stimulated to release stored calcium ions from bone
Intentional response -> rate of intestinal absorption of calcium increases
Kidney response -> kidneys retain calcium ions

92
Q

What is the response to high calcium ion levels in plasma?

A

Parafollicular cells in the thyroid gland secret calcitonin

93
Q

What are the 3 responses to release of calcitonin?

A

Bone response -> osteoclasts inhibited while osteoblasts continue to lock calcium ions in bone matrix
Intestinal response -> rate of intestinal absorption decreases
Kidney response -< kidneys allow calcium loss

94
Q

What is diabetes?

A

The absence, deficit or resistance to insulin leading to hyperglycaemia

95
Q

What is type 1 diabetes linked with?

A

Viral infection and autoimmune disease

96
Q

What is type 2 diabetes linked with?

A

Obesity, age and ethnicity

97
Q

What are the risk factors of type 1 diabetes?

A

Family history, viral infection

98
Q

What are the risk factors of type 2 diabetes?

A

Obesity, hypertension, poor lifestyle, diet