Endocrine histology Flashcards Preview

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Flashcards in Endocrine histology Deck (55):
1

Exocrine gland means

it secretes onto a surface, directly or through a duct

2

Endocrine gland means

it secretes internally and is ductless

3

What are the two types of hormones?

Circulating
Local

4

What are the two subgroups of local hormones and what do they mean?

Paracrine- acts on other cells
Autocrine- acts on itself

5

The hypothalamus is the ______ control center.

Autonomic

6

The hypothalamus is connected to the _____ via the infindibulum

pituitary gland

7

The pituitary gland is also known as the what?

the hypophysis

8

What are the two parts of the pituitary gland?

Anterior and posterior pituitary

9

What are the three parts of the anterior pituitary?

Pars distalis
Pars intermedia
Pars tuberalis

10

What are the two parts of the posterior pituitary gland?

Pars nervosa
Infindibulum

11

The anterior lobe of the hypophysis develops from where?

The roof of the mouth

12

The release of hormones from the anterior pituitary is stimulated by _____ ______ and suppressed by ______ _____. from the ______.

releasing hormones
inhibiting hormones
Hypothalamus

13

The regulating hormones from the hypothalamus reach the anterior lobe of the pituitary via what?

Hypothalamo-hypophyseal portal system

14

What are the two groups of secretaory cells in pars distalis? What is the main difference?

Chromophils
Chromophobes
This is based on staining affinity- color loving or color hating

15

What are the two different types of chromophils?

Basophils- affinity for basic dyes
Acidophils- affinity for acidic dyes

16

What are the three types of basophils?

Gonadotropic cells
Corticotropic cells
Thyrotropic cells

17

What are the two types of acidophils?

Somatotropic cells
Mammotropic cells

18

What percent of pars distalis are chromophobes?

50%

19

T/F the posterior pituitary doesn't synthesize hormones?

Truthhhe.

20

What does the posterior pituitary do?

It stores and releases hormones

21

What are the two hormones of the posterior pituitary?

Oxytocin
Antidiuretic hormone (ADH)

22

Where are the hormones of the posterior pituitary synthesized?

The (neurosecretory neurons of the) hypothalamus

23

What are Herring bodies?

They are dilated portions of the axon that store hormones

24

What is the pineal gland?

It regulates sleep and wake cycles (circadian rhythm)

25

What is the major hormone produced by the pineal gland?

Melatonin

26

What are the two types of cells in the pineal glands?

Pinealocytes (95%)
Interstitial (glial) cells (5%)

27

The pineal gland looks like what?

Brain sand

28

What are the two parts of the adrenal glands?

Medulla
Cortex

29

The cortex of the adrenal glands is made up of what?

Steroid secreting cells

30

The medulla of the adrenal glands contain what type of cells?

The catecholamine secreting cells

31

The adrenal medulla produces three ______ hormones.

Catecholamine

32

Which zone of the adrenal cortex secretes glucocoriticoids (mainly cortisol)?

The Zona fasciculata

33

From outside to inside, what are the layers/zones of the adrenal gland?

Zona glomerulosa
Zona fasciculata
Zona reticularis
Adrenal medulla

34

T/F the adrenal medulla is a modified sympathetic ganglion of the autonomic nervous system?

True

35

Does the adrenal medulla develop from the same embryonic tissue as the other sympathetic ganglia of the body?

Yep

36

What are the cells called in the adrenal medulla that cluster around blood vessels and release hormones?

Chromaffin cells

37

What is the endocrine portion of the pancreas called?

The islets of Langerhans

38

T/F the pancreas has both exocrine and endocrine functions.

True

39

What are the three types of cells of the islets of Langerhans?

Beta/B cells
Alpha/A cells
Delta/D cells

40

What do B cells do?

B cells synthesize and secrete insulin

41

What do alpha cells do?

A cells synthesize and secrete glucagon

42

What do D cells do?

D cells synthesize and secrete somatostatin

43

What type of cell is most commonly found in the pancreas?

Beta cells

44

What does insulin do?

It signals the cells for the uptake of sugar into the cell and to make glycogen

45

What does glucagon do?

It signals for the breakdown of glycogen and glucose gets released into the blood?

46

What does somatostatin do?

It inhibits insulin and glucagon secretion- think statin-stationary- no secretion

47

What are the two thyroid hormones?

T4- thyroxin
T3- Tri-iodothyronine

48

T3 and T4 are important for what?

Growth, basal metabolic rate

49

Parafollicular cells are responsible for the production of and are found where?

Calcitonin (CT)
Thyroid gland

50

What does calcitonin do?

It decreases the level of calcium in the blood by inhibiting osteoclast activity and encouraging bone deposition

51

How is calcitonin regulated?

Negative feedback- high levels of blood calcium stimulate the secretion of calcitonin while low levels of Ca inhibit the secretion of CT

52

What are the two parathyroid cell types?

Chief cells- produce parathyroid hormone
Oxyphil cells- no idea what it does

53

Which cells produce PTH?

The chief cells of the parathyroid gland

54

What does PTH do?

It increases blood calcium by stimulating osteoclast activity and allowing the kidneys to leave more calcium in the blood

55

How is PTH regulated?

Negative feedback