Histology Endocrine System

Question 1

What type of glands secrete onto a surface, either directly or via a duct

Answer 1

exocrine glands

Question 2

What type of glands secrete internally, are ductless, secrete hormones, and primarily utilize the cardiovascular system for distribution?

Answer 2

endocrine glands

Question 3

There are two types of hormones. They are:

Answer 3

circulating hormones and local hormones (local include paracrine and autocrine)

Question 4

What types of body parts does the hypothalamus control?

Answer 4

visceral functions

Question 5

What types of functions does the hypothalamus include?

Answer 5

regulation of body temp, food intake, water balance/thirst, sleep-wake cycles, sexual behavior, and endocrine system function

Question 6

the hypothalamus is the major link between what two systems?

Answer 6

endocrine and nervous

Question 7

What is considered the “command center for the endocrine system”

Answer 7

hypothalamus

Question 8

How many hormones are produced by the hypothalamus?

Answer 8

9

Question 9

Briefly describe the number of hormones that go to each part of the pituitary, where they come from, and what about them is unique?

Answer 9

All of the hormones to the pituitary are coming from the hypothalamus. There are 5 RELEASING hormones going to the anterior pituitary, 2 INHIBITING hormones going to the anterior pituitary, and 2 OTHER hormones going to the posterior pituitary

Question 10

What connects the hypothalamus to the pituitary gland?

Answer 10

infundibulum

Question 11

Answer 11

Question 12

The pituitary gland is also known as what?

Answer 12

hypophysis

Question 13

What sits in the hypophyseal fossa within the sella turcia of the sphenoid bone?

Answer 13

pituitary gland

Question 14

Name the three divisions of the anterior pituitary gland

Answer 14

1) pars distalis (bulk of anteior lobe… epithelial cells interspersed with fenestrated capillaries)
2) pars intermedia (thin remnant)
3) pars tuberalis (forms a collar or sheath around infundibulum, most cells here are basophilic gonadotropic cells)

Question 15

Name the two divisions of the posterior pituitary gland

Answer 15

1) pars nerosa (neurosecretory axons and their endings)
2) infundibulum (neurosecretory axons forming hypothalamo-hypophyseal tracts)

Question 16

Answer 16

Question 17

Of the anterior and posterior pituitary lobes, which is the larger and more well defined of the two?

Answer 17

posterior

Question 18

What is the embryological name for the future posterior pituitary? anterior?

Answer 18

posterior: neurohypophyseal bud
anterior: hypophyseal pouch

Question 19

At what week in embryological development do the hypophyseal pouch and neurohypophyseal bud form?

Answer 19

week 3

Question 20

During what period of pregnancy have the anterior and posterior pituitary fully formed?

Answer 20

fetal period

Question 21

The pituitary gland (hypophysis) is derived in part from an outpocketing of the _____ lining the roof of the mouth called the _____ pouch and in part from an outpocketing of the _____ lining the floor of the hypothalamus called the neurohypophyseal bud

Answer 21

ectoderm

hypophyseal

neuroectoderm

Question 22

Which lobe of the pituitary develops from the roof of the mouth?

Answer 22

anterior lobe

Question 23

Hypothalmic hormones travel down the axons of _____ neurons to the axon terminals where they exit into the pituitary via exocytosis

Answer 23

neurosecretory

Question 24

The hormones of the hypothalamus diffuse into the hypophyseal portal system via what?

Answer 24

primary plexus of the hypophyseal portal system (fenestrated capillaries)

Question 25

Which structure brings hormones from the primary plexus of the hypophyseal portal system to the pars distalis of the pituitary gland?

Answer 25

secondary plexus of the hypophyseal portal system

Question 26

What are the two large groupings of secretory cells stored in the pars distalis based on staining affinity?

Answer 26

1) chromophils 2) chromophobes

Question 27

What are the two divisions of the chromophilic secretory cells in the pituitary gland?

Answer 27

1) basophils (gonadotropic, corticotropic, & thyrotropic) 2) acidophils (somatotropic, mammotropic)

Question 28

Name the 7 hormones of the anterior pituitary

Answer 28

1) HGH 2) TSH (thyroid stim) 3) FSH (follicle stim) 4) LH 5) Prolactin 6) ACTH (adrenocorticotrophic) 7) MSH (melanocyte-stimulating)

Question 29

What percent of the pars distalis cells are chromophobes?

Answer 29

50%

Question 30

HGH is secreted by _____ and is an \_\_\_\_\_

Answer 30

somatotrophs, acidophil

Question 31

TSH is secreted by _____ and is an \_\_\_\_\_

Answer 31

thyrotrophs, basophil

Question 32

FSH is secreted by _____ and is an \_\_\_\_\_

Answer 32

gonadotrophs, basophil

Question 33

LH is secreted by _____ and is an \_\_\_\_\_

Answer 33

gonadotrophs, basophil

Question 34

Prolactin is secreted by _____ and is an \_\_\_\_\_

Answer 34

lactotrophs, basophil

Question 35

ACTH is secreted by _____ and is an \_\_\_\_\_

Answer 35

corticotrophs, basophil

Question 36

MSH is secreted by _____ and is an \_\_\_\_\_

Answer 36

corticotrophs, basophil

Question 37

acidophils stain _____ and basophils stain \_\_\_\_

Answer 37

light pink purple/blue

Question 38

What is the main role of HGH and what does it stimulate the secretion of?

Answer 38

it stimulates the liver, muscle, cartilage, bone, and other tissues to synthesize and secrete IGFs which promote growth of body cells, tissue repair, etc

Question 39

What is the main role of TSH?

Answer 39

it stimulates synthesis and secretion of thyroid hormone by the thyroid gland

Question 40

What is the main role of FSH?

Answer 40

in femalse, it initiates development of oocytes and induces ovarian secretion of estrogens. In males, it stimulates testes to produce sperm

Question 41

What is the main action of LH?

Answer 41

in females, it stimulates secretion of estrogens and progesterone, ovulation, and formation of corpus luteum. In males, it stimulates testes to produce testosterone

Question 42

What is the main role of PRL (prolactin)?

Answer 42

Together with other hormones, it promotes milk secretion by the mammary glands

Question 43

What is the role of ACTH?

Answer 43

it stimulates secretion of glucocorticoids by the adrenal cortex

Question 44

What is the main role of MSH?

Answer 44

the exact role is unknown but it can influence brain activity and can cause darkness of skin in high doses

Question 45

be able to distinguish between the pars nervosa and pars distalis on a stained tissue section (remember that the pars distalis stains darker and more densel than the pars nervosa)

Answer 45

Question 46

What hormones does the posterior pituitary *synthesize?*

Answer 46

none

Question 47

What two hormones does the posterior pituitary gland store and secrete

Answer 47

Oxytocin and ADH

Question 48

What is the most common cell type in the posterior pituitary?

Answer 48

pituicytes (a type of glial cell with many branches resembling an astrocyte that associates with the fenestrated capillaries)

Question 49

Where are hormones stored in the posterior pituitary?

Answer 49

the axon terminal as well as the dilated portions of the axons near the terminals called HERRING BODIES

Question 50

What stimulates the secretion of oxytocin?

Answer 50

uterine distension and stimulation of nipples

Question 51

What is the principal action of oxytocin?

Answer 51

to stimulate smooth muscle contraction of uterus and cells in mammary glands

Question 52

What controls the secretion of ADH?

Answer 52

elevated blood osmotic pressure, dehydration, loss of blood volume, pain, or stress

Question 53

What is the principal action of ADH

Answer 53

to conserve body water by decreasing uring volume, lowering perpiration, and raising blood pressure by constricting arterioles

Question 54

What are the two major divisions of the adrenal glands?

Answer 54

cortex and medulla

Question 55

The the cortex or the medulla the larger of the two areas within the adrenal gland?

Answer 55

the cortex is larger

Question 56

Is the cortex or the medulla the part of the adrenal gland that secretes steroids?

Answer 56

the cortex secretes steroids

Question 57

Does the cortex or the medulla of the adrenal gland secrete catecholamine?

Answer 57

the medulla secretes catecholamine

Question 58

label the layers of the adrenal gland

Answer 58

Question 59

name the bottom 4 adrenal layers and their respective secretions

Answer 59

Question 60

be able to distinguish histological sections of the glomerular zone, the fascicular zone, and the retiular zone of the adrenal gland

Answer 60

Question 61

What is the main role of aldosterone?

Answer 61

to regulate Na+and K+ and water in order to control blood pressure

Question 62

What is the main role of cortisol?

Answer 62

to regulate glucose and fatty acid metabolism as well as suppress the immune system in response to stress

Question 63

What is the main role of DHEA?

Answer 63

to assist in early growth of axillary and pubic hair in both sexes

Question 64

What is the main role of epinephrine and norepinephrine?

Answer 64

to intensify sympathetic responses in various parts of the body

Question 65

The adrenal medulla is a modified _____ ganglion of the ____ nervous system

Answer 65

sympathetic, autonomic

Question 66

The adrenal medulla develops from _____ cells

Answer 66

neural crest!

Question 67

Do the cells in the adrenal medulla have axons?

Answer 67

No. Instead of releasing neurotransmitters via neural axons, they use modified neurons called CHROMAFFIN CELLS which cluster around blood vessels and release hormones directly into the blood stream. These chromaffin cells are controlled by sympathetic PREGANGLIONIC neurons which allow quick signaling

Question 68

From which part of the adrenal gland are epinephrine and norepinephrine secreted?

Answer 68

adrenal MEDULLA

Question 69

What cells within the pancreas are endocrine?

Answer 69

Islets of langerhan

Question 70

What is characteristic about the staining of the islets of langerhan within the pancreas?

Answer 70

they tend to stain pale compared to the exocrine portion (the pancreatic acini)

Question 71

What cells of the pancreas are exocrine?

Answer 71

pancreatic acinar cells

Question 72

What are the three principle cells of the islets of langerhans?

Answer 72

1) Beta (B) cells. Make up 70% of the islet, synthesize and secrete insulin 2) Alpha (A) cells. Make up 17% of the islet, synthesize and secrete glucagon 3) Delta (D) cells. Make up 7% of islet, synthesize and secrete somatostatin (identical to growth hormone-inhibiting hormone from hypothalamus)

Question 73

Insulin _____ blood glucose levels as it signals for an acceleration of _____ transport into cells and the conversion of glucose into \_\_\_\_\_

Answer 73

lowers glucose glycogen (aka glycogenesis)

Question 74

What chemical synthesized and released in the pancreas raises blood sugar levels?

Answer 74

glucagon (from alpha cells)

Question 75

What chemical synthesized and released from the pancreas inhibits glucagon and insulin secretion?

Answer 75

somatostatin (from delta cells)

Question 76

know the approximate appearance of pancreatic islet cells

Answer 76

Question 77

The walls of the thyroid gland are made up of follicular cells. What cell type are these?

Answer 77

simple squamous to low columnar

Question 78

What are the two thyroid hormones?

Answer 78

1) T4 (4 atoms of iodione) 2) T3 (3 atoms of iodine)

Question 79

The gel-like mass found within thyroid follicles is called what?

Answer 79

colloid

Question 80

Parafollicular cells (C cells) within the thyroid are responsible for the production of what?

Answer 80

calcitonin

Question 81

be able to identify and label the types of cells and membranes within a histological section of thyroid tissue

Answer 81

Question 82

\_\_\_\_\_ feedback mechanism control the release of calcitonin from parafollicular (C) cells within the thyroid gland

Answer 82

negative feedback

Question 83

High blood Ca levels _____ the release of calcitonin

Answer 83

stimulate

Question 84

Low blood Ca levels ____ the secretion of calcitonin

Answer 84

inhibit

Question 85

What two cell types are located within parathyroid glands?

Answer 85

1) chief cells (most numerous, pale-staining) 2) oxyphil cells (larger, very acidophilic, unknown function)

Question 86

What cells produce parathyroid hormone?

Answer 86

chief cells in the parathyroid gland

Question 87

What is the role of parathyroid hormone

Answer 87

parathyroid hormone increases the level of Ca in the blood by stimulating bones to release Ca. PTH also prevents Ca loss from blood into urine