Week 5 - Endocrine System

Question 1

What is the endocrine system?

Answer 1

Group of tissues and glands that secrete hormones. Capillaries pick up the hormones and carry them by bulk flow.

Question 2

If the secreting cell is a neuronal cell, what kind of signalling is it?

Answer 2

Neuroendocrine signalling

Question 3

Describe classic endocrine signalling

Answer 3

Secreting cell secretes hormones into surrounding interstitial fluid. Blood vessels pick it up and brings them to target tissues.

Cells of target tissues have receptors for the hormone

Question 4

Name two water soluble hormones

Answer 4

Insulin
Epinephrine

Question 5

Where are the receptors of water-soluble hormones

Answer 5

On the surface of the cell, since it cant cross the lipid membrane of cells

Question 6

Where are the receptors of lipid-soluble hormones

Answer 6

Inside the cell, since it can cross the membrane

Question 7

Name an example of lipid-soluble hormones

Answer 7

Steroidal hormones

Question 8

Describe paracrine signalling. Name examples

Answer 8

TRAVELS BY DIFFUSION

Secreting cell releases signalling molecules that travel to nearby crlls to trigger a response

Mast cells and neutrophils

Question 9

Describe autocrine signalling. Name an example

Answer 9

TRAVELS BY DIFFUSION

Secreting cell releases signalling molecules that trigger a response on itself.

Cytokines from helper T cells

Question 10

Describe synaptic signalling

Answer 10

TRAVELS BY DIFFUSION

Secreting cell is a neuron and the route traveled is the synaptic cleft

Question 11

What is gastrin?

Answer 11

Hormone that makes parietal cells secrete hydrochloric acid to lower stomach PH

Question 12

What are secretin and CCK

Answer 12

Two hormones that slow the rate of peristalsis and promote the secretion of bicarbonate ions from the pancreas.

Additionally, CCK is responsible to trigger gallbladder to secrete bile into duodenum

Question 13

Describe blood glucose homeostasis

Answer 13

Blood sugar rises

Beta cells of pancreas secrete insulin

Insulin binds to surface receptors of cells:
liver and muscle cells respond to the insulin and store the glucose for later use.

Blood glucose levels fall

Alpha cells releases glucagon

Glucagon initiates the release of glycogen, gets turned into glucose

Question 14

Describe blood calcium homeostasis

Answer 14

Calcium levels fall

Parathyroid gland secrete PTH

PTH stimulate osteoblasts to release calcium

PTH targets kidney cells to reabsorb vitamin D (vitamin D triggers epithelial cells in villi to absorb more calcium)

PTH gets nephron to reabsorb calcium

Question 15

What happens if you have too much calcium

Answer 15

It can calcify in soft tissues

Question 16

What is the command center of the endocrine system?

Answer 16

Hypothalamus and Pituitary gland

Question 17

What does the posterior pituitary gland do?

Answer 17

Receives hormones from hypothalamus and then blood capillaries soak them up to take them away

Question 18

What does the anterior pituitary gland do?

Answer 18

Neurohormones from hypothalamus go to anterior pituitary gland capillaries, triggering a response.

SYNTHESIZES HORMONES

CLASSIC ENDOCRINE SIGNALLING

Question 19

What is oxytocin

Answer 19

Hormone involved in the release of milk from mammillary glands

Question 20

Describe the short-term response to stress

Answer 20

Nervous system secretes epinephrine and norepinephrine.

Blood vessels bring to liver

Epinephrine tells liver to break down glycogen to get glucose

Epinephrine tells muscles to dilate for more energy

Epinephrine constricts arterioles of digestion, excretion, etc

Question 21

Describe the long-term response to stress

Answer 21

Persistently high blood pressure bc of high production of aldosterone (which causes reabsorption of salt)

Production of cortisol

Question 22

Endocrine vs exocrine glands?

Answer 22

Exocrine secrete substances (fluids)
Endocrine produce hormones

Question 23

What is particular about oogenesis cytokinesis

Answer 23

It’s asymmetrical- polar body and oocyte

Question 24

Where does spermatogenesis take place?

Answer 24

Seminiferous tubules

Question 25

How long does it take for spermatids mature?

Answer 25

24 days

Question 26

What stimulates follicle growth?

Answer 26

FSH and LH

Question 27

What hormone triggers ovulation?

Answer 27

Luteinizing hormone (LH)

Question 28

What does estradiol do?

Answer 28

Makes endometrium get thicker

Question 29

In what phase does the endometrium get thicker?

Answer 29

Proliferation stage

Question 30

What happens during the luteal phase?

Answer 30

More blood flow, Secrete fluids