Unit 4: Cell Signaling

Question 1

How many types of cell signaling and what are they?

Answer 1

3. Direct signaling, local signaling, and long distance signaling

Question 2

What is direct signaling?

Answer 2

Directly contacting other cells

Question 3

Examples of direct signaling?

Answer 3

Cell junction - cytoplasm

Cell-cell - immune system. T cells tell body to produce antibodies.

Question 4

What is local signaling?

Answer 4

Close but not connected signaling.

Question 5

Example of local signaling?

Answer 5

Synaptic: in brain. Nerves interact by neurotransmission by sending a direct signal.

Question 6

What is long distance signaling?

Answer 6

Signaling that occurs from long distance.

Question 7

Example of long distance signaling?

Answer 7

Across the bloodstream like the endocrine system which sends hormone signaling like the adrenal gland.

Question 8

What are the three stages of cell communication?

Answer 8

Reception/communication
Transduction
Response

Question 9

What are signal transduction pathways?

Answer 9

STP’s link signal reception with cellular response.

Many include protein modification and/or phosphorylation cascades which amplify the signal.

STP’s influence how a cell responds to the environment.

Question 10

What is the difference between phosphates/phosphorylation cascades?

Answer 10

Attaching phosphate groups to molecules like a proteins activates them.

Protein kinases attach phosphates to molecules/activate.

Protein phosphates remove a phosphate from a molecule/deactivate.

Question 11

What can STP’s result in and what is programmed cell death called?

Answer 11

A change in gene expression or cell function.

Apotasis