Question 1

Which of the following best describes the role of a sensor in the homeostasis feedback mechanism?

Accepted Answer

It detects changes in the internal environment and sends information to the integrating center.

Question 2

A patient is experiencing rapid changes in blood glucose levels. Which type of cell communication is most likely responsible for the immediate regulation of this process?

Accepted Answer

Endocrine signaling

Question 3

Which of the following is an example of a contact-dependent signal in cell communication?

Accepted Answer

Membrane-bound ligand binding to a receptor on an adjacent cell

Question 4

A ligand binds to a membrane receptor and triggers a cascade involving second messengers. Which of the following best describes this process?

Accepted Answer

Signal transduction pathway

Question 5

Which equation best represents the relationship between substrate concentration and reaction rate in a system showing saturation kinetics?

Accepted Answer

$$V = V_{max} \frac{[S]}{K_m + [S]}$$

Question 6

Which of the following scenarios best illustrates paracrine signaling?

Accepted Answer

A cell releases a chemical signal that affects neighboring cells in the same tissue.

Question 7

A competitive antagonist binds to a receptor. What is the most likely outcome?

Accepted Answer

The receptor is blocked, preventing the agonist from binding and activating the receptor.

Question 8

Which of the following is NOT a type of cell communication described in the study materials?

Accepted Answer

Photosynthetic signals

Question 9

Which of the following best describes the specificity of ligand-receptor interactions?

Accepted Answer

Ligands bind only to receptors with complementary shapes and chemical properties.

Question 10

Which of the following is an example of an ectocrine signal?

Accepted Answer

A pheromone released into the environment to affect another organism

Question 11

A cell receives a signal via a ligand-gated ion channel. What is the immediate effect?

Accepted Answer

Change in membrane potential due to ion flow

Question 12

Which of the following is a correct example of a second messenger in signal transduction?

Accepted Answer

cAMP

Question 13

A cell is exposed to two different ligands that compete for the same receptor. What is the most likely outcome?

Accepted Answer

The ligand with higher affinity and concentration will predominantly bind and activate the receptor.

Question 14

Which of the following best describes negative feedback in homeostasis?

Accepted Answer

A process that counteracts changes to maintain stability.

Question 15

Which type of membrane receptor is most likely to activate a G-protein and initiate a second messenger cascade?

Accepted Answer

G-protein coupled receptor (GPCR)

Question 16

A hormone is released into the bloodstream and affects cells in distant organs. This is an example of:

Accepted Answer

Endocrine signaling

Question 17

Which of the following best explains the concept of saturation in receptor-ligand interactions?

Accepted Answer

All receptors are occupied, and increasing ligand concentration does not increase the response.

Question 18

Which pathway is most likely to be activated when a hydrophobic ligand binds to its receptor?

Accepted Answer

Activation of intracellular receptors leading to gene transcription

Question 19

Which of the following is a correct sequence for the signal transduction pathway involving a second messenger?

Accepted Answer

Ligand binds receptor → G-protein activation → Adenylyl cyclase activation → cAMP production

Question 20

Which of the following best describes the function of gap junctions in cell communication?

Accepted Answer

They allow direct electrical and chemical communication between adjacent cells.

CH 6 Study Guide

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드