Cell Signaling

Question 1

Define cell signaling

Answer 1

Essentially cell communication

Question 2

What do all cells receive and respond to ?

Answer 2

Signals from their environments

Question 3

Define ligand

Answer 3

A molecule that bind to receptors by the signal perceived by the cell.

Question 4

What are receptors ?

Answer 4

They identify or bind to ligands

Question 5

What are the four types of cell signaling ?

Answer 5

Direct, endocrine, paracrine, and Autocrine signaling

Question 6

What is direct signaling ?

Answer 6

molecules (ligands) on the surface of one cell interact with receptors on the surface of another cell.

Question 7

What is endocrine signaling ?

Answer 7

Ligands that are secreted by one cell, but travel considerable distance before interacting with the target cell

Question 8

What is paracrine signaling

Answer 8

The ligand is secreted by one cell but acts on a nearby cell with receptors on its surface

Question 9

What is Autocrine signaling

Answer 9

the cell that secretes the ligand also expresses the receptor

Question 10

What is signal Transduction ?

Answer 10

passing the signal from the ligand to the internal part of the cell to get some type of cell response

Question 11

What response is not need to be a transcription factor for turning on a gene ?

Answer 11

Cell response

Question 12

Are RAS and RAF immediately down or upstream of the receptor ?

Answer 12

Downstream

Question 13

We have a cell receptor that binds to a growth factor. What type of receptor is it ?

Answer 13

Probably a tyrosine kinase receptor

Question 14

What is RAS ?

Answer 14

A kinase

Question 15

How is RAF activated ?

Answer 15

activated when growth factor binds top tyrosine kinase receptor.

Question 16

What type of protein is RAS ?

Answer 16

G-protein

Question 17

How is RAS activated ?

Answer 17

When GTP is exchanged for GDP

Question 18

What type of molecule is MEK ?

Answer 18

A kinase

Question 19

What type of early mutants was RAS discovered to be a cause of ?

Answer 19

Known to be the most common mutant for Cancer

Question 20

Define Loss of Function

Answer 20

A mutation that causes a protein to lose function and is a recessive tumour repressor mutation

Question 21

What type of factor is NF-kB and where does it want to be ?

Answer 21

It’s a transcription factor and wants to be in the nucleus.

Question 22

All transcription factors have what type of binding domain ?

Answer 22

DNA Binding domain.

Question 23

What is one of the many genes that is turned on by NF-kB ?

Answer 23

I-kB gene

Question 24

Where is the nuclear receptor found and what type of factor is it ?

Answer 24

The cytoplasm and it’s a transcription factor