Endocrine System Flashcards Preview

Histology > Endocrine System > Flashcards

Flashcards in Endocrine System Deck (67):
1

Functions of endocrine system

Maintain body homeostasis, help the body react to stress and regulate growth and development, including sexual development

2

How does the endocrine system achive its functions

Through the production and secretion of hormones

3

What are the main types of hormones produced by the endocrine system

Protein and glycoprotein, small peptide, derivatives of amino acids and steroids derived from cholesterol

4

What does the endocrine system consist of

Major endocrine organs, organs with partial endocrine roles and the diffuse endocrine system

5

What is the origin of most endocrine tissue

Epithelial

6

Some major endocrine glands

Pituitary, hypothalamus, pineal, thyroid, parathyroid, thymus, adrenal glands, pancreas and gonads

7

Why is the pituitary known as the master gland

As its hormones regulate the activity of many other endorine glands

8

Where is the pituitary located

Sella turcica of the sphenoid bone

9

Another name for the pituitary

Hypophysis

10

What are the two lobes of the pituitary

Anterior/adenohypothysis and posterior/neurohypophysis

11

What is the posterior lobe developed from

Downwards growth of the hypothalamus

12

What attaches the posterior lobe to the hypothalamus

Pituitary stalk

13

What does the anterior lobe form from

An upwards pocket of epithelium in the roof of the oral cavity called Rathke's pouch

14

What controls the secretion from the anterior pituitary

Hormones released from the hypothalamus

15

How are the hormones from the hypothalamus delivered to the anterior pituitary

In high concentrations through they hypothalamic-hypophyseal portal system

16

What hormones does the pituitary secrete

Oxytocin, ADH, growth hormones, prolactin, gonadotropins, ACTH and TSH

17

What are the hypothamic hormones that regulate the anterior pituitary

Growth-releasing hormone, somatostatin, thyrotropic-releasing hormone, corticotrophin-hormone, alopanine and gonadotropin-releasing hormone

18

What does the anterior pituitary consist of

Packed secretory cells interspersed with fenestrated endothelium-lined vascular sinuses

19

What are the cells of the anterior pituitary

Acidophils, basophils and chemophobes

20

What are acidophils and basophils known as collectively

Chromophils

21

What does the posterior pituitary consist of

Axons of nerve cells in the suraoptic and paraventricular nuclei of the hypothalamus

22

What are the special glial cells within the posterior pituitary

Pituicytes

23

What are the swellings in the axons of the posterior pituitary

Herring bodies

24

What are herring bodies

Aggregations of oxytocin or ADH

25

What is the portion of the pituitary between the anterior and posterior lobes

Pars intermedia

26

What is the pars intermedia

The remnants of the lumen of Rathke pouch

27

What is contained within the pars intermedia

Follicles that contain a colloid

28

What is the functional unit of the thyroid gland

Thyroid follicle

29

What is the thyroid follicle

A spherical space lined by epithelial cells that are low cuboidal when inactive

30

What regulates the basal cell metabolism and heat production

T3 and T4

31

What are C cells

Cells adjacent to the follicle cells
They are within the basal lamina that surrounds the follicle

32

What do C cells produce

Calcitonin

33

What function does calcitonin have

Inhibits osteoclast activity and lowers blood calcium

34

What are C cells derived from

Neural crests

35

What are the parathyroid glands

Four oval glands on the posterior surface of the thyroid gland

36

What do the parathyroid glands produce

Parathyroid hormone

37

Function of parathyroid hormone

Increases serum calcium by stimulating the release of calcium from bone, increasing renal calcium absorption and increasing calcium absorption from the gut

38

What are the 3 cells within the parathyroid glands

Principle/chief cells, oxyphils and occasional adipose cells

39

Chief cells

Small, lightly stained cells with dark, central nuclei
Secrete PTH

40

Oxyphils

Larger eosinophil cells
Appear at puberty and become more numerous with age
Have large numbers of mitochondira

41

What surrounds the parathyroid gland

Connective tissue capsule

42

What forms the adrenal cortex

Epithelial cells

43

What forms the adrenal medulla

Neural crest cells

44

What surrounds the adrenal glands

A thick capsule with connective tissue trabeculae extending inwards through the cortex

45

Layers of the adrenal cortex

Zona glomerulosa
Zona fasciculata
Zona reticularis

46

What type of hormones are secreted by the zona granulosa

Mineralocorticoids

47

Function of mineralocorticoids

Electrolyte and fluid homeostasis

48

What is the main mineralocorticoid

Aldosterone

49

Function of aldosterone

Promotes Na+ retention in the distal convoluted tubule of the kidney

50

What type of hormones does the zona fasciculata produce

Glucocorticoids

51

Unction of glucocorticoids

Involved in many aspects of metabolism

52

What is the main glucocorticoid produced

Cortisol

53

Control of secretion of cortisol

ATCH from the anterior pituitary

54

What type of hormones does the zona reticularis produce

Sex hormones

55

What does the adrenal medulla reinforce

The actions of the sympathetic nervous system at times of stress

56

Cells of the adrenal medulla

Slightly basophilic and arranged in cords and nests
Consist of granules of adrenaline and noradrenaline

57

What type of gland is the pancreas

Both exocrine and endocrine

58

What does the endocrine pancreas consist of

Scattered islands of tissue called islets of Langerhan

59

Blood supply of the islets of Langerhan

Have a rich blood supply

60

Secretory cells of the pancreas

Lightly stained and spherical-clustered cells

61

Principle cells within the pancreatic islets

Insulin secreting cells, glucagon secreting cells and somatoststin secreting cells

62

Function of insulin secreting cells

Lowering of blood glucose

63

Function of glucagon secreting cells

Elevation of blood glucose

64

Function of somatostatin secreting cells

Inhibit insulin and glucagon secretion

65

What is an antibody

A identifiable marker on or in a specific cell

66

What hormone do the testes produce and what cell produces it

Testosterone and the Leydig cells

67

What hormones do the ovaries produce

Oestrogen and progesterone