Question 1

Which type of light microscope is best suited for visualizing living, unstained cells and their internal structures, and why?

Accepted Answer

Phase contrast microscope, because it amplifies differences in refractive index to visualize living cells.

Question 2

A student wants to isolate bacterial ribosomes from a sample. Which technique should she use, and what is the principle behind it?

Accepted Answer

Cell fractionation, which separates cellular components based on size and density using centrifugation.

Question 3

Why is being multicellular advantageous compared to simply being a larger single cell, in terms of surface area to volume ratio?

Accepted Answer

Multicellularity increases the surface area to volume ratio, allowing efficient exchange of materials.

Question 4

Which of the following is NOT a difference between prokaryotic and eukaryotic cells?

Accepted Answer

Prokaryotic cells have a nucleus; eukaryotic cells do not.

Question 5

The plasma membrane is primarily composed of which molecules, and what is the function of the 'sugar coating'?

Accepted Answer

Phospholipids, proteins, and carbohydrates; the 'sugar coating' (glycocalyx) aids in cell recognition and protection.

Question 6

Which statement best describes the nuclear membrane's permeability and its importance?

Accepted Answer

The nuclear membrane is selectively permeable, allowing mRNA and ribosomal subunits to exit while protecting DNA.

Question 7

Ribosomes are found in which locations within a cell, and what is their primary function?

Accepted Answer

Attached to the rough ER, free in the cytoplasm, and inside mitochondria; they synthesize proteins.

Question 8

What distinguishes the rough endoplasmic reticulum (ER) from the smooth ER, and what is the main function of the rough ER?

Accepted Answer

Rough ER has ribosomes attached, synthesizing proteins for secretion or membrane insertion.

Question 9

A cell is observed to have abundant smooth ER. Which function is most likely enhanced in this cell?

Accepted Answer

Synthesis of lipids and detoxification of drugs.

Question 10

Which best describes the role of the Golgi apparatus in the endomembrane system?

Accepted Answer

It modifies, sorts, and packages proteins and lipids received from the ER for transport.

Question 11

Lysosomes are essential for cellular recycling. Which reaction occurs inside lysosomes, and what is the result?

Accepted Answer

Hydrolysis reactions break down macromolecules into their monomers.

Question 12

A macrophage engulfs a bacterium through phagocytosis. What typically happens to the bacterium after engulfment?

Accepted Answer

It is enclosed in a vesicle and digested by lysosomal enzymes.

Question 13

Autophagy and apoptosis are related cellular processes. Which statement best explains their relationship?

Accepted Answer

Autophagy recycles cellular components, while apoptosis is programmed cell death; both maintain cellular health.

Question 14

Which organelles are part of the endomembrane system, and how are materials transported between them?

Accepted Answer

Nuclear envelope, ER, Golgi apparatus, lysosomes, and vesicles; materials are transported via membrane-bound vesicles.

Question 15

According to the endosymbiotic theory, what evidence supports the origin of mitochondria and chloroplasts in eukaryotic cells?

Accepted Answer

Both organelles contain their own DNA and ribosomes, similar to prokaryotes.

Question 16

Peroxisomes are abundant in liver cells. What compound do they produce, and why is this important?

Accepted Answer

Hydrogen peroxide ($$\mathrm{H_2O_2}$$), which is used to detoxify harmful substances.

Question 17

Which cytoskeletal protein fiber is the strongest, and what is its primary function?

Accepted Answer

Intermediate filaments; they provide structural support and maintain cell shape.

Question 18

How do cilia and flagella move, and which human cells possess these structures?

Accepted Answer

They move via dynein motor proteins sliding microtubules; sperm cells have flagella, respiratory tract cells have cilia.

Question 19

Which two major proteins help an amoeba move and are also found in muscle cells, and how do they function?

Accepted Answer

Actin and myosin; they interact to produce contraction and movement.

Question 20

Which type of cell junction creates a barrier that is fairly impermeable to extracellular fluid movement, and which allows direct cytosolic communication between cells?

Accepted Answer

Tight junctions create a barrier; gap junctions allow direct communication.

BIOL 1406 Unit 2 Study Guide – Cell Structure and Function

Study Guide - Practice Questions

Study Guide - Flashcards