Anatomy 18 - The Endocrine System Flashcards Preview

Second Year - Anatomy CA21007 > Anatomy 18 - The Endocrine System > Flashcards

Flashcards in Anatomy 18 - The Endocrine System Deck (76):
1

What is the endocrine system

A system of ductless glands that regulate bodily function via hormones

2

What are the main functions of the endocrine system

It maintains homeostasis, it helps the body react to stress, it is a major regulator of growth and development and it controls physical and behavioural activities

3

How does it maintain homeostasis

By regulating activities such as the concentration of chemicals in body fluids and the metabolism of proteins, lipids and carbohydrates

4

What are the tissues/glands within the endocrine system known as

Endocrine glands

5

What do endocrine glands do

They secrete chemicals into extracellular space

6

What are the chemicals secreted by the glands called

Hormones

7

How is it determined which cells are acted on by specific hormones

Only cells with the compatible receptors will be affected by specific hormones

8

What are the three ways in which endocrine glands are stimulated

Hormonal, humoral and neural

9

What is hormonal stimulation

When the stimulation of a gland occurs through hormones being secreted from somewhere else e.g. the pituitary stimulating the thyroid

10

What is humoral stimulation

The stimulation of a target gland through the presence of a molecule within the bloodstream

11

What is neural stimulation

Stimulation of a gland via direct signals from the nervous system

12

What are the central glands of the endocrine system

The pineal and pituitary glands

13

What are the peripheral glands of the endocrine system

The thyroid, parathyroid, thymus, adrenal/suprarenal glands and the pancreas

14

Where is the pineal gland situated

In the roof of the 3rd ventricle

15

What are the cells within the pineal gland called

Pinealocytes

16

What is the major secretory product of the pineal gland

Melatonin

17

What is melatonin involved in

Regulating sleep

18

What is the pituitary gland split into

The anterior and posterior pituitary

19

What is the pineal gland involved in regulating

Day/night cycles

20

What is the anterior pituitary composed of

Glandular tissue

21

Function of the anterior pituitary

To manufacture and release hormones

22

Hormones released from where control secretion of hormones from the anterior pituitary

The ventral hypothalamus

23

Through what system is the secretion of hormones from the anterior pituitary controlled

The hypophyseal portal system

24

What is the posterior pituitary composed of

Neural tissue

25

Function of posterior pituitary

Acts as a storage area and releases neurohormones

26

Where are the neurohormones released by the posterior pituitary made

The hypothalamus

27

Where is the pituitary located

In the hypophyseal fossa of the sella turcia of the sphenoid bone

28

What takes up hormones released by the pituitary

The bloodstream

29

What hormones are secreted by the anterior pituitary

Growth hormone, thyroid stimulating hormone, adrenocorticotrophic hormone, follicle stimulating hormone, luteinising hormone and prolactin

30

What regulates growth hormone

Growth hormone releasing hormone and growth hormone inhibiting hormone

31

What does growth hormone target

The liver, muscle, bone and cartilage

32

What regulates thyroid stimulating hormone

Thyroid releasing hormone and feedback

33

What is thyroid regulating hormone involved in regulating

Metabolism

34

What regulated follicle stimulating hormone

Gonadotrophin-releasing hormone and feedback

35

What does follicle stimulating hormone target

The testes/ovaries

36

What does follicle stimulating hormone regulate

The development, growth, maturation and reproductive processes of the body

37

What occurs due to a lack of follicle stimulating hormone

Failure of sexual maturation

38

What is adrenocorticotrophic hormone regulated by

Corticotrophin-releasing hormone and feedback

39

What does adrenocorticotrophic hormone act on

The adrenal cortex

40

What causes the production of adrenocorticotrophic hormone

Stress

41

What does the release of adrenocorticotrophic hormone cause increased production of

Corticosteroids

42

What is luteinising hormone regulated by

GnRH and feedback

43

Where does luteinising hormone target

The ovaries/testes

44

What does luteinising hormone stimulate the production of

Testosterone, the development of the corpus luteum and causes ovulation

45

What does a lack of luteinising hormone cause

Failure of sexual maturation

46

What is prolactin regulated by

Prolactin releasing hormone and prolactin inhibiting hormone

47

Where does prolactin target

The mammary glands

48

What hormones does the posterior pituitary release

Oxytocin and antidiuretic hormone

49

What regulates oxytocin

The hypothalamus and also by uterine stretching and suckling

50

Where does oxytocin target

The uterus and breasts

51

What does oxytocin stimulate

Birth and milk production

52

What regulates ADH

The hypothalamus by the blood osmolarity and volume

53

Where does ADH target

The kidneys

54

What causes a release of ADH

The body being dehydrated

55

What secretes thyroid hormone

Follicle cells

56

Where does thyroid hormone effect

All cells except the brain, sleep, uterus and thyroid

57

What is the thyroid hormone involved in

The metabolism of carbohydrates, proteins and lipids

58

What do parafollicular cells secrete

Calcitonin

59

What is the function of calcitonin

To lower the level of Ca++ in the blood

60

What is the function of parathyroid hormone

To increase the level of Ca++ in the blood

61

What does the thymus secrete and what is it essential for

Peptide hormones and for normal development of T lymphocytes and the immune response

62

What is involved in the short term stress response

The adrenal medulla

63

What does the adrenal medulla cause

An increase in heart rate and blood pressure, it causes the liver to convert glycogen to glucose, causes the dilation of the bronchioles, causes an increase in alertness and metabolism

64

What does the pancreatic islets produce

Glucagon and insulin

65

What is glucagon involve in

The synthesis of alpha cells

66

What is insulin involve in

The synthesis of beta cells

67

What do beta cells cause

The blood sugar levels to be lowered

68

What do alpha cells cause

The blood sugar level to increase

69

What does the adrenal cortex synthesise

Corticosteroids

70

How many corticosteroids are produced by the adrenal cortex

24

71

What are corticosteroids synthesised from

Cholesterol

72

What are the three categories of corticosteroids

Mineralocorticoids, glucocorticoids and sex steroids

73

Function of mineralocorticoids

Control electrolyte balance

74

Function of glucocorticoids

Stimulate fat and protein catabolism and release fatty acids and glucose into the blood

75

What stimulates the secretion of glucocorticoids

Adrenocorticotropic hormone

76

What is involved in the long term stress response

The adrenal cortex