Embryology & Histology: Endocrine- Reynolds

Question 1

What is the primary function of the endocrine system?

Answer 1

Aid in establishment and maintenance of homeostasis

Question 2

What is the speed of onset for the endocrine system?

Answer 2

Seconds to hours

Question 3

What is the duration of the endocrine system?

Answer 3

Can range from hours to weeks even if the secretion ceases

Question 4

What is a horomone?

Answer 4

A long distance chemical secreted into the blood and transported to specific receptor sites and affects the function of the cell/tissue

Question 5

Describe the three main functions of the hypothalamus

Answer 5

Direct innervation of the adrenal gland
Secrete oxytocin and ADH
Indirect control through regulation hormones

Question 6

What is the hypothalamus mainly composed of and where is it located?

Answer 6

Nervous tissue

Base of the brain

Question 7

Where is the pituitary gland located?

Answer 7

At the base of the hypothalamus

Question 8

What is the anterior pituitary gland (adenohypophysis) made of and what is its function?

Answer 8

Glandular epithelium
Contains chromophobes and chromophils in pars distalis
Secretes hormones

Question 9

What is the posterior pituitary gland (neurohypophysis) made of and what is its function?

Answer 9

Nervous epithelium
Contains Herring bodies (extensions from the hypothalamus)
Acts as a reservoir for the hypothalamus and contains capillaries to transport hypothalamus horomones

Question 10

Developmentally, where did the anterior pituitary (adenohypophysis) come from?

Answer 10

Rathke’s pouch
Made from ectoderm
Invagination of the stomatodeum

Question 11

Developmentally, where did the posterior pituitary (neurohypophysis) come from?

Answer 11

Infundibulum
Made from ectoderm
Extension of the diencephalon

Question 12

Where was the parathyroid derived from?

Answer 12

The 3rd (inferior) and 4th (superior) pouch

Question 13

Where was the thymus derived from?

Answer 13

The 3rd pouch

Question 14

Where was the parafollicular cells derived from and what structure do they belong to?

Answer 14

The 4th pouch
Thyroid
In development they are also known as ultimopharyngeal bodies

Question 15

What do parafollicular cells secrete?

Answer 15

calcitonin

Question 16

What does the thyroid gland make and where is it located?

Answer 16

Calcitonin, T3, and T4
Underneath the larynx
Activated by TSH from the anterior pituitary

Question 17

What are the two types of cells associated with the thyroid?

Answer 17

Follicular- T3 and T4

Parafollicular- calcitonin

Question 18

What are the associated cells of the parathyroid?

Answer 18

Cheif/Principle Cells and Oxyphil Cells
They secrete PTH
Signal the production of osteoclast stimulating factor

Question 19

What are the parts of the adrenal glands and what are the functions of each

Answer 19

Medulla- catecholamines

Cortex- steroid hormones

Question 20

How do the parts of the adrenal glands develop?

Answer 20

Cortex first starts out as the primidium cortex and then gets engulfed by the definitive cortex (mesoderm)

Medulla is from migrating neural crest cells and migrates towards the center of the cortex (ectoderm)

Question 21

What is unique about the pancreas?

Answer 21

It is both exocrine and endocrine

Question 22

Describe the development of the pancreas

Answer 22

Dorsal bud and Ventral bud fuse off of the duodenum

Ventral contains two buds
Annulus pancreas is when the two ventral buds migrate opposite directions around the duodenum

Question 23

What are the associated cells of the pancreas?

Answer 23

Islets of Langerhans

Alpha- glucagon
Beta- insulin (most)
Delta- somatostatin (least)