Integration, Communication, Homeostasis

Question 1

Second messenger that binds Calcium channels of endoplasmic reticulum

Answer 1

Inositol triphosphate (IP3)

Question 2

GPCR also uses lipid-derived 2nd messengers. Name the 3 messengers.

Answer 2

Phospholipase C
Diaglycerol (DAG)
Inositol triphosphate (IP3)

Question 3

Name the important intracellular signal

Answer 3

Calcium

Question 4

Calcium enters the cell via what kind of channels?

Answer 4

Gated channels

Question 5

Short-acting paracrine/autocrine signaling molecule that acts close to where they are produced

Answer 5

Soluble Gases

Question 6

Calcium binds to ___ or other regulatory proteins to trigger cell function

Answer 6

Calmodulin

Question 7

Functions of nitric oxide

Answer 7

Vasodilator
Neurotransmitter/neuromodulator in the brain

Question 8

Function of carbon monoxide

Answer 8

Activates GUANYLYL CYCLASE and targets SMOOTH muscle and neural tissue

Question 9

Function of hydrogen sulfide

Answer 9

Targets cardiovascular system to relax blood vessels

Question 10

Synthesis process of eicosanoids

Answer 10

Arachidonic acid cycle

Question 11

Arachidonic acid is produced by the action of this enzyme

Answer 11

PLA2

Question 12

How are leukotrienes produced? What is their role?

Answer 12

Produced via action of lipoxygenase on AA; role in asthma/anaphylaxis

Question 13

How are prostanoids produced? What is their role?

Answer 13

Produced via action of COX on AA; prevent inflammation via inhibiting COX

Question 14

The alpha isoform has a higher affinity for _______

Answer 14

Norepinephrine

Question 15

The beta isoform has higher affinity for _____

Answer 15

Epinephrine

Question 16

Blocks receptor entirely - no repsonse

Answer 16

Antagonist

Question 17

Can activate a receptor but takes up binding site. Can still produce a response.

Answer 17

Agonist

Question 18

Cell’s ability to respond to chemical signal is limited by # of receptors for that signal

Answer 18

Saturation

Question 19

Decrease in # of receptors
(Cell can remove receptors via endocytosis)

Answer 19

Down Regulation

Question 20

Target cells insert more receptors into the membrane

Answer 20

Up-regulation

Question 21

Regulation is not “on” or “off” but is regularly mediated up or down

Answer 21

Tonic Control

Question 22

What is antagonistic control and give example

Answer 22

How systems regulate and control opposing actions

Ex: parasympathetic and sympathetic NS

Question 23

What happens to blood vessels under tonic control with decreased and increased signals?

Answer 23

Decreased - dilation
Increased - constricts

Question 24

Compares input signal with setpoint

Answer 24

Integrating center

Question 25

3 major components of reflex pathway

Answer 25

Input, Integrating Center, Output

Question 26

Simple reflex system uses ___ OR ____ ; complex uses ___

Answer 26

Simple carried out by EITHER endocrine or nervous; complex uses both

Question 27

The transmission of info from one side of a membrane to another using membrane proteins

Answer 27

Signal Transduction

Question 28

The 2nd messenger is formed via intracellular molecules and can alter what 3 things?

Answer 28

Ion channels, calcium, enzyme activity

Question 29

The extracellular signal is 1st messenger that activates what 2 things?

Answer 29

Protein kinases Amplifier enzymes

Question 30

List the order of basic signal transduction pathway

Answer 30

External signal Receptor Transducer Amplifier RESPONSE

Question 31

Function of protein kinases

Answer 31

Transfer phosphate group from ATP to a protein

Question 32

Function of amplifier enzymes

Answer 32

Activate intracellular 2nd messengers

Question 33

Signal transduction pathways form a ____

Answer 33

Cascade

Question 34

Ligand binding to receptor channels changes _____

Answer 34

Ion permeability

Question 35

Most signal transduction uses what kind of proteins?

Answer 35

G proteins

Question 36

Many lipophobic hormones use what kind of pathways for signal transduction?

Answer 36

GPCR - cAMP pathways

Question 37

Chemicals released by NEURONs into the blood for action at distant targets

Answer 37

Neurohormones

Question 38

The only means by which electrical signals can pass directly from cell to cell

Answer 38

Gap Junctions

Question 39

Example of a paracrine signal

Answer 39

Histamine (released by damaged cells)

Question 40

Peptides synthesized by all nucleated cells in response to stimulus (regulatory protein)

Answer 40

Cytokines

Question 41

Which are made on demand and which are stored in advance in the endocrine cells?

Answer 41

Cytokines - on demand Classic hormones - in advance

Question 42

Membrane receptor where ligand binding opens an ion channel or alters enzyme activity

Answer 42

G protein - coupled

Question 43

Membrane receptor in which ligand binding opens or closes the channel

Answer 43

Receptor-channel

Question 44

4 methods of cell to cell communication

Answer 44

Gap junctions Contact-dependent signals Local communication Long Distance communication