Question 1

Which of the following best describes the three main stages of cell signaling in the correct order?

Accepted Answer

Reception, signal transduction, response

Question 2

A mutation causes a cell to lack functional insulin receptors. What is the most likely immediate effect on glucose uptake?

Accepted Answer

Glucose uptake will decrease because the cell cannot detect insulin.

Question 3

Which type of signaling involves hormones traveling through the bloodstream to reach distant target cells?

Accepted Answer

Endocrine signaling

Question 4

Testosterone is a hydrophobic molecule. Where would you expect to find its receptor?

Accepted Answer

In the cytoplasm or nucleus of the target cell

Question 5

Which of the following is a common second messenger in signal transduction pathways?

Accepted Answer

Cyclic AMP (cAMP)

Question 6

What is the primary role of protein kinases in signal transduction?

Accepted Answer

To transfer phosphate groups from ATP to proteins

Question 7

A cell is exposed to a hydrophilic signaling molecule. Where is its receptor most likely located?

Accepted Answer

On the plasma membrane

Question 8

Which of the following best explains why cell-surface receptors require signal transduction pathways?

Accepted Answer

Because the receptor cannot leave the plasma membrane

Question 9

Which plasma membrane receptor type is most likely to form a dimer upon ligand binding and trigger multiple signaling pathways?

Accepted Answer

Receptor tyrosine kinases

Question 10

What is the source of the phosphate group transferred during a kinase reaction?

Accepted Answer

ATP

Question 11

Which of the following is a likely cellular response to signal transduction in the cytoplasm?

Accepted Answer

Opening or closing of an ion channel

Question 12

If a mutation prevents the phosphorylation of kinases in the insulin signaling pathway, what is the most likely outcome?

Accepted Answer

Glucose uptake by cells will be impaired

Question 13

Which of the following best describes the effect of phosphorylation on the serine side chain of a protein?

Accepted Answer

It changes a polar hydroxyl group to a charged phosphate group

Question 14

Which of the following is NOT a function of cellular signaling?

Accepted Answer

Synthesizing ATP directly from glucose

Question 15

A patient with type 1 diabetes is unable to produce insulin. Which stage of cell signaling is directly affected?

Accepted Answer

Signal production

Question 16

Which of the following is a reason why different cell types can respond differently to the same signaling molecule?

Accepted Answer

They have different collections of proteins

Question 17

What is the main advantage of a multistep signal transduction pathway?

Accepted Answer

It amplifies the signal and allows for regulation

Question 18

Which of the following would most likely occur if the insulin signaling pathway is inhibited?

Accepted Answer

Blood sugar levels will remain high

Question 19

Which of the following best explains why people with diabetes may feel fatigued more easily than non-diabetics?

Accepted Answer

They have defective insulin signaling, reducing cellular glucose uptake

Question 20

Which of the following is a function of scaffolding proteins in signal transduction?

Accepted Answer

They increase the efficiency of signal transduction by grouping relay proteins

Cell Signaling: Mechanisms and Biological Importance

Study Guide - Practice Questions