Signalling

Question 1

what are the three steps of cell communication?

Answer 1

Reception, transduction, and response

Question 2

Describe the one direct cell pathway of communication

Answer 2

gap junctions: they are passages between cells, they are responsible for providing quick messages straight through the cytoplasm.

Question 3

describe the main characteristics of steroid lignds

Answer 3

1. derived from cholesterol
2. lipophilic, so they cant be stored in vesicles
3. since they are lipophlic, they can diffuse across the membrane and bind to intracellular receptors
4. they act as gene transcription factors

Question 4

3 types of steroids

Answer 4

mineralocorticoids, glucocorticoids, and sex hormones

Question 5

what are eicosanoids derrived from?

Answer 5

phospholipids

Question 6

what path do the eicosanoids follow?

Answer 6

paracrine (one cell to another)

Question 7

what are eicosanoids biggest role?

Answer 7

they signal pain and inflammation

Question 8

what are pain eicosanoids called

Answer 8

prostaglandins

Question 9

what enzyme converts phosopholipids into eicosanoids?

Answer 9

phospholipase II

Question 10

what are characteristics of protein signals?

Answer 10

1. most of them are enzymes

2. they are hydrophilic, so they can be stored in vesicles

Question 11

How can protein enzymes be regulated in the cell

Answer 11

an inactive peptide comes along and binds to the enzymes sequence, rendering the enzyme inactive until needed. Once the enzyme is needed, the inactive part drops off, and the enzyme then folds and goes about its business

Question 12

What are 3 characteristics of amine messengers, and what is an example?

Answer 12

1. the are recognized by an amine group
2. they are synthesized from amino acid
3. they are hydrophilic, so they can be stored

Question 13

what are the only amine ligands that arent hydrophilic

Answer 13

thyroid hormones

Question 14

What two paths are purines used by

Answer 14

paracrine and neuronal

Question 15

What are gases usually in the cell?

Answer 15

waste

Question 16

what four modes of transport are used by the gases

Answer 16

direct, paracrine, neuronal, and endocrine

Question 17

What kind of ligand must a intracellular receptor have?

Answer 17

A small or a lipophillic one

Question 18

What often occurs when a lignad binds with its intracellular receptor which is position near or on the nuclear membrane?

Answer 18

the ligand and receptor form a unit that turns into a transcription factor

Question 19

what are 2 characteristics of lipid rafts?

Answer 19

1. sphingolipids and cholesterol are in high amounts, to keep everything sticking together
2. the phospholipids are much longer to accomodate the large proteins

Question 20

what is the difference between autocrine and paracrine?

Answer 20

Autocrine: the cell secretes a ligand that binds to a receptor on itself
Paracrine: ligand secreted by a cell, and the ligand goes to another cell

Question 21

what is endocrine signaling?

Answer 21

lignad passes through transportaion system and binds to a specific cell

Question 22

what is an example of an exocrine gland?

Answer 22

a sweat gland

Question 23

which group of ligands can act as transcription factors?

Answer 23

steroids

Question 24

what are two examples of well known purines

Answer 24

caffeine and uric acid

Question 25

what are the three types of transmembrane protein receptors?

Answer 25

Ligand gated ion channels
receptor-enzyme, and
g-protein coupled receptors

Question 26

what is a major role a intracellular receptor bound to a lignad?

Answer 26

it can become a transcription factor

Question 27

What are the four classes of receptors?

Answer 27

Ligand gated ion channels, enzyme receptor, G-protein coupled receptors, and intracellular receptors

Question 28

What is a product of guanylate cyclase?

Answer 28

converts GTP into cGMP, bro