Chapter 6

Question 1

What are effectors?

Answer 1

Muscles and other tissues controlled by integrating centre

Question 2

What is the pathway of cell-to-cell communication?

Answer 2

Input, integrating, output, response

Question 3

What are the proteins of the body

Answer 3

The bodies workhorse

Question 4

What are electrical signals

Answer 4

They have the ability to change cell membrane potential

Question 5

What are chemical signals

Answer 5

Molecules secreted by cells
and received by target cells (ligands)

Question 6

Gap Junctions

Answer 6

Clusters of intercellular channels that allow direct diffusion of ions and small molecules between adjacent cell

Question 7

What are Gap Junctions?
(localized communication)

Answer 7

Allows direct cytoplasmic transfer of electrical and chemical signals between adjacent cells

Question 8

What are Contact-Dependant molecules? (localized communication)

Answer 8

Surface molecules on one cell membrane bind to surface molecules on another cell membrane

Question 9

Autocrine vs Paracrine (localized communication)

Answer 9

Autocrine - signaling regulates cellular growth and development
Paracrine - signaling is involved in immune responses and blood clotting

Question 10

What is Long Distance Communication?

Answer 10

Usually between the endocrine and nervous system, them and electrical signals carried by nerve cells

Question 11

What do gap junctions create?

Answer 11

Cytoplasmic Bridges

Question 12

What is the Endocrine System? (long distance)

Answer 12

Hormones transport system, into blood or target cells with the correct receptors

Question 13

What is a neurotransmitters? (long distance)

Answer 13

Chemicals from neutrons that diffuse across the small gap in target cells

Question 14

What is a neurohormone? (long distance)

Answer 14

Chemicals released by neurons into blood for action at distant targets

Question 15

What does crine mean?

Answer 15

Secretion

Question 16

What are CAM’s?

Answer 16

Cell Adhesion Molecules

Question 17

Synchronous Contraction

Answer 17

Gap junctions where electrical signals are rapidly transmitted via protein pores

Question 18

Desmosomes

Answer 18

Surrounds sarcomeres and allows force to be transferred

Question 19

Where are gap junctions found?

Answer 19

Heart and smooth muscle

Question 20

What is a Sarcomere?

Answer 20

The basic contractile unit of muscle fibre

Question 21

Can long distance communication be electrical or chemical?

Answer 21

Yes

Question 22

Where is neurocrine release from?

Answer 22

Neurons

Question 23

What are cytokines?

Answer 23

Peptides that are both local and long-distance communication

Question 24

Lipophobic Signal Molecules do what?

Answer 24

They diffuse and then bind to cytosolic receptors or nuclear receptors

Question 25

What are intracellular signal receptors?

Answer 25

Stimuli with ligands and IC receptors and then bind to the response elements of DNA

Question 26

What does Transduction mean?

Answer 26

The process by which a virus transfers genetic material from one bacterium to another

Question 27

What are first messengers?

Answer 27

First messengers are extracellular factors, often hormones or neurotransmitters, such as epinephrine, growth hormone, and serotonin

Question 28

What are second messengers?

Answer 28

Small molecules and ions that relay signals received by cell-surface receptors to effector proteins

Question 29

What are cascades?

Answer 29

Transduction pathways form an cascade like a ladder

Question 30

What are amplification?

Answer 30

Small amount of signal to have a large effect

Question 31

How many categories are there of membrane receptors?

Answer 31

- receptor-channel; binding opens or closes channel - G protein - receptor- enzyme; activates IC enzyme - integrin receptor; alters enzyme or cytoskeleton

Question 32

What are G protein-coupled receptors? (GPCR)

Answer 32

Opens ion channels and alters enzyme activities

Question 33

How does signal transduction work using g-proteins?

Answer 33

1. molecule binds to GPCR activating g-protein 2. g-protein turns on adenylyl cyclase, and amplifier enzyme 3. AC then converts ATP to cyclic AMP 4. cAMP activates protein kinase A 5. Protein kinase A phosphorylates other proteins leading to cellular response

Question 34

What is a TK receptor and what does it do? Who uses this?

Answer 34

Tyrosine kinase transfers a phosphate group from ATP to tyrosine. Used by insulin

Question 35

Does calcium work as an intracellular messenger?

Answer 35

It does, calcium induces through gated channels, gets released within cardiac muscles, store in ER

Question 36

What is an ephemeral signal molecule?

Answer 36

A soluble gas are short acting paracrine or autocrines, the best known one is NO. Activates cGMP

Question 37

Does target response depend on the target receptor?

Answer 37

Yes