Cell signaling and communication

Question 1

What is cell signaling?

Answer 1

The process by which cells communicate with each other to send and receive information that will lead to a cellular effect.

Question 2

True or False: Cell signaling can occur through direct contact between cells.

Answer 2

True (e.g. gap junctions)

Question 3

Fill in the blank: The molecules that transmit signals between cells are called __________.

Answer 3

ligands

Question 4

Name four main types of cell signaling

Answer 4

Autocrine, paracrine, endocrine and synaptic signaling.

Question 5

Which type of signaling involves hormones traveling through the bloodstream?

Answer 5

Endocrine signaling.

Question 6

What is the role of receptors in cell signaling?

Answer 6

Receptors bind signaling molecules (ligands) and initiate a cellular response by changing conformation

Question 7

Multiple Choice: Which of the following is NOT a type of receptor? A) G-protein coupled receptor B) Ion channel receptor C) DNA receptor D) Enzyme-linked receptor

Answer 7

C) DNA receptor

Question 8

True or False: Signal transduction is the process of converting an extracellular signal into a functional response inside the cell.

Answer 8

True

Question 9

What is the function of second messengers in cell signaling?

Answer 9

They amplify the signal by rapid synthesis of small molecules (such as cyclic AMP) or increase in intracellular concentration of calcium

Question 10

Fill in the blank: The __________ pathway is a common signaling pathway that involves the activation of protein kinases.

Answer 10

MAPK

Question 11

Multiple Choice: Which molecule is commonly involved in the activation of G-protein coupled receptors? A) ATP B) cAMP C) cGMP D) GTP

Answer 11

D) GTP

Question 12

What is the primary role of neurotransmitters in cell signaling?

Answer 12

To activate specific receptors, which are ligand activated ion channels

Question 13

What is the difference between endocrine and paracrine signaling?

Answer 13

Endocrine signaling involves hormones traveling through the bloodstream, while paracrine signaling involves signals affecting nearby cells.

Question 14

What is a molecular switch?

Answer 14

A small protein, such as Ras, which can be activated by a cell signal and inactivates itself, usually by hydrolyzation of GPT to GDP

Question 15

What is the particularity of tyrosin-kinase receptors?

Answer 15

The intracellular domain of the receptor acts as a kinase, able to phosphorylate other proteins. When ligand binds and two receptors join together (dimerize), they are able to cross phosphorylate each other, initiating downstream signaling