Question 1

Which of the following best describes the function of the cell membrane (plasma membrane)?

Accepted Answer

It acts as a boundary between the inside and outside of the cell, regulating the movement of substances.

Question 2

Which component of the phospholipid bilayer is hydrophilic?

Accepted Answer

Phosphate head group

Question 3

A scientist observes a protein that spans the entire cell membrane and assists in transporting molecules across. What type of protein is this?

Accepted Answer

Transmembrane protein

Question 4

Which organelle is responsible for synthesizing ATP and contains its own DNA?

Accepted Answer

Mitochondria

Question 5

If a cell loses its ribosomes, which process would be most directly affected?

Accepted Answer

Protein synthesis

Question 6

Which of the following is a function of membrane proteins?

Accepted Answer

Acting as identity markers for the immune system

Question 7

A cell is observed to have a large number of lysosomes. What is the most likely function of this cell?

Accepted Answer

Digestion of bacteria and worn-out organelles

Question 8

Which of the following best describes the 'Fluid Mosaic Model' of the cell membrane?

Accepted Answer

Membrane constituents can move around, and proteins and lipids are distributed in a mosaic pattern.

Question 9

During cell division, which structure organizes the spindle apparatus?

Accepted Answer

Centrosome

Question 10

Which of the following organelles is non-membranous and is the site of protein synthesis?

Accepted Answer

Ribosome

Question 11

A mutation affects the structure of microtubules in a cell. Which function would be most directly impaired?

Accepted Answer

Movement of cilia and flagella

Question 12

Which of the following is true regarding chromatin?

Accepted Answer

It is DNA uncoiled and not individually visible, present when the cell is not dividing.

Question 13

Which organelle is considered the 'cellular post office' because it sorts, packages, and delivers proteins and lipids?

Accepted Answer

Golgi apparatus

Question 14

Which of the following best explains why cholesterol is important in the cell membrane?

Accepted Answer

It adds stability to the cell membrane.

Question 15

A patient has a genetic disorder affecting the smooth endoplasmic reticulum. Which process is most likely to be disrupted?

Accepted Answer

Synthesis of lipids and steroid hormones

Question 16

Which formula correctly represents the calculation of surface area ($$A) of a $$spherical cell with radius $$r$$?

Accepted Answer

$$A = 4 \pi r^2$

Question 17

Which of the following is NOT a function of cytoskeleton proteins?

Accepted Answer

Synthesis of ATP

Question 18

Which organelle contains a double membrane and is the site of ATP synthesis?

Accepted Answer

Mitochondria

Question 19

Which of the following best describes the difference between rough and smooth endoplasmic reticulum?

Accepted Answer

Rough ER has ribosomes attached and synthesizes proteins; smooth ER lacks ribosomes and synthesizes lipids and steroid hormones.

Question 20

A cell is observed to have a large nucleus and several nucleoli. What is the primary function of the nucleolus?

Accepted Answer

Synthesis of ribosomal RNA (rRNA) and assembly of ribosomes

Unit 3- The Cell: Structure, Components, and Functions

Study Guide - Practice Questions