Endocrine system Quiz #4

Question 1

In the human body, communication occurs between what 2 major systems?

Answer 1

1.) nervous system
2.) endocrine system

Question 2

What are hormones?

Answer 2

chemical messengers secreted by glands, released into the circulatory system to elicit a response upon target cells.

Question 3

There are 2 types of glands, what are they?

Answer 3

1.) Exocrine
2.) Endocrine

Question 4

What is the difference between exocrine and endocrine glands?

Answer 4

1.) exocrine glands secrete substances into ducts or onto body surfaces
(salivary glands, sweat glands)
2.) endocrine glands lack ducts. secrete substances into interstitial fluid which diffuses into circulatory system
(hormones)

Question 5

What are circulating hormones?

Answer 5

.transported through blood to distant target cells
.these hormones are endocrine hormones
.they may last for minutes or hours
.they are inactivated by the liver and excreted by the kidney

Question 6

what are local hormones?

Answer 6

.released very close to their target cells
.diffuse through interstitial fluid to the target cell without entering blood
.usually inactivated very quickly
. usually associated with immunity

Question 7

What are the two categories of local hormones?

Answer 7

1.) autocrine
(act on same cell which secreted them)
2.) paracrine
(acts on other neighbouring cells)

Question 8

What are the 4 main classes of hormones?

Answer 8

1.) Steroids
2.) Amines
3.) Peptides and proteins
4.) eicosanoids

Question 9

What are some examples of steroid hormones?

Answer 9

.aldosterone
.cortisol
.androgens
.vitamin D
.testosterone
.estrogens and progesterone

Question 10

what are steroid hormones derived from?

Answer 10

cholesterol. Thus they are fat soluble and cross the phospholipid bilayer easily.

Question 11

What are some examples of Amine hormones?

Answer 11

These hormones are simple derivatives of amino acids. .thyroid hormones
.epinephrine and norepinephrine

Question 12

What are some examples of peptide/protein hormones?

Answer 12

consist of chains of amino acids.
insulin
pituitary hormones
hypothalamic hormones

Question 13

What are some examples of eicosanoid hormones?

Answer 13

derived from a 20 carbon fatty acid called arachidonic acid. act as paracrine or autocrine hormones in most tissues of the body. produced by all body cells except RBC’s.
2 families of eicosanoids:
1.) leukotrienes
( promote inflammation and participate in all allergic responses)
2.) prostaglandins
(promote inflammation regulate body temperature, influence blood clot formation)

Question 14

What are hormone receptors?

Answer 14

only target cells of a particular hormones have receptors that bind and recognize that hormone.
receptors are constantly synthesized and degraded.
Receptors are large protein or glycoprotein molecules.W

Question 15

what is down regulation?

Answer 15

When a hormone is present in excess, the number of hormone receptors may decrease.
This down regulation decreased the responsiveness of target cells to the hormone.
down regulation can sometimes prevent overstimulation of a glad or tissue.

Question 16

What is up regulation?

Answer 16

When a hormone is deficient the number of hormone receptors may increase.
up regulation makes a target tissue more sensitive to a hormone.

Question 17

What are 3 hormone interactions in the body?

Answer 17

1.) permissive effect
2.) synergistic effect
(2+ hormones work together to produce effect ex: progesterone/oxytocin/prolactin work together to cause milk production)
3.) antagonistic effect
( 2 hormones have the opposite effect on target cells ex: glucagon/insulin)

Question 18

What happens to hormones once they have caused an effect?

Answer 18

must be removed.
1.) liver alters or degrades hormones-especially steroids
2.) many peptide hormones are taken up and degraded by the kidney
3.) fast acting hormones like epinephrine are inactivated by specific degrading enzymes circulating in the blood and excreted in urine
4.) man of the larger peptide hormones like insulin are degraded within their target cells