Chemical messengers and receptors

Question 1

Hormones are released by what 5 things

Answer 1

endocrine glands, epithelial, nervous, muscle, and connective tissues

Question 2

Neurohormones are released by what kind of tissue

Answer 2

nervous tissue

Question 3

Neurotransmitters are relased by what 2 kinds of tissue

Answer 3

neurons and specialized epithelial cells (taste buds, inner ear hairs, etc.)

Question 4

What are the 5 molecular types of hormones

Answer 4

protein, glycoprotein, polypeptide, amino acid derived, and lipid hormones

Question 5

The receptors for proteins, glycoproteins, polypeptides, and most amino acid-derived hormones are located ____ because they can’t diffuse through the plasma membrane

Answer 5

within the plasma membrane

Question 6

The receptors for lipids (steroids and fatty acid derivatives) as well as gases like NO and CO, are ___ receptors since lipid-soluble substances can diffuse through the plasma membrane

Answer 6

intracellular

Question 7

What are the 4 things that affect receptor/ligand binding?

Answer 7

specificity, competition, affinity, and saturation

Question 8

____ activate the receptors for a given chemical signal

Answer 8

agonists

Question 9

____ inhibit the receptors for a given chemical signal

Answer 9

antagonists

Question 10

In _____, the number of receptor proteins increases and the cells become more sensitive to a chemical signal

Answer 10

up-regulation

Question 11

In _____, the rate at which receptors are made can increase after a cell is exposed to a chemical signal

Answer 11

up-regulation

Question 12

In ___, the number of receptor proteins decreases and the cells become less sensitive to a chemical signal

Answer 12

donw-regulation

Question 13

Down-regulation occurs in one of two ways. They are what:

Answer 13

1-decrease rate of receptor gene expression

2-internalization–the receptor and bound ligand is taken into the cell by receptor-mediated endocytosis

Question 14

When a hormone binds to its receptor, the GDP on the alpha subunit of the G protein is replaced with GTP, and this ____ the G protein

Answer 14

activates

Question 15

After the G protein is activated, the G protein separates from the receptor, and then what happens?

Answer 15

The alpha subunit separates from the gamma and beta subunits

Question 16

Eicosanoids are derived from ____

Answer 16

the fatty acids from the phospholipids that make up the plasma membranes

Question 17

Eicosanoids function in both ____ and ____ responses

Answer 17

paracrine and autocrine

Question 18

The three types of eicosanoids are ___, ___, and ___

Answer 18

prostaglandins, thromboxanes, and leukotrienes

Question 19

____ are involved in vascular actions and inflammation

Answer 19

prostaglandins

Question 20

____ are involved in blood clotting and other vascular actions

Answer 20

thromboxanes

Question 21

___ mediate allergic and inflammatory reactions

Answer 21

leukotrienes