Question 1

Which of the following statements best explains why cells are considered the fundamental units of life?

Accepted Answer

Cells are the smallest structures that can carry out all activities required for life.

Question 2

A scientist wants to study the internal structure of mitochondria at very high resolution. Which type of microscope should they use and why?

Accepted Answer

Transmission electron microscope (TEM), because it passes electrons through the specimen, revealing internal structures.

Question 3

Which of the following best describes the main difference between prokaryotic and eukaryotic cells?

Accepted Answer

Eukaryotic cells have membrane-bound organelles, including a nucleus, while prokaryotic cells do not.

Question 4

A cube-shaped cell increases its length from 1 $$\mum to 2$$ $$\mum. By $$what factor does its surface area-to-volume ratio change?

Accepted Answer

It decreases by a factor of 2.

Question 5

Which organelle is primarily responsible for synthesizing lipids and detoxifying drugs in liver cells?

Accepted Answer

Smooth endoplasmic reticulum (smooth ER)

Question 6

A mutation prevents the formation of nuclear pores in a eukaryotic cell. Which process would be most directly affected?

Accepted Answer

Transport of RNA and proteins between the nucleus and cytoplasm

Question 7

Which of the following best explains the endosymbiont theory for the origin of mitochondria and chloroplasts?

Accepted Answer

Mitochondria and chloroplasts originated from free-living prokaryotes that were engulfed by ancestral eukaryotic cells.

Question 8

A cell is observed to have a large number of peroxisomes. Which function is this cell most likely specialized for?

Accepted Answer

Detoxification of harmful substances by converting hydrogen peroxide to water

Question 9

Which of the following structures is directly involved in the movement of chromosomes during cell division?

Accepted Answer

Microtubules

Question 10

A plant cell is placed in a hypotonic solution. Which structure prevents the cell from bursting?

Accepted Answer

Cell wall

Question 11

Which of the following best describes the function of lysosomes in animal cells?

Accepted Answer

They digest macromolecules and recycle damaged organelles.

Question 12

A muscle cell contracts by the interaction of which two cytoskeletal components?

Accepted Answer

Actin (microfilaments) and myosin

Question 13

Which of the following is a function of the Golgi apparatus?

Accepted Answer

Modifying, sorting, and packaging proteins for secretion

Question 14

Which of the following best explains why animal cells require an extracellular matrix (ECM)?

Accepted Answer

The ECM provides structural support, helps cells adhere, and facilitates communication between cells.

Question 15

A researcher observes that a certain animal tissue has cells tightly pressed together, preventing leakage of extracellular fluid. Which type of intercellular junction is most likely present?

Accepted Answer

Tight junctions

Question 16

Which of the following best describes the role of plasmodesmata in plant cells?

Accepted Answer

They allow the passage of water, small solutes, and some proteins and RNA between adjacent cells.

Question 17

A mutation disrupts the function of dynein in a cell. Which process would be most directly affected?

Accepted Answer

Movement of cilia and flagella

Question 18

Which of the following is a key feature that allows mitochondria to efficiently produce ATP?

Accepted Answer

The inner membrane is highly folded into cristae, increasing surface area for enzymes involved in ATP synthesis.

Question 19

Which of the following best explains why cells are typically small in size?

Accepted Answer

A high surface area-to-volume ratio allows efficient exchange of materials with the environment.

Question 20

A cell is observed to have a large central vacuole, chloroplasts, and a cell wall. Which type of cell is this most likely to be?

Accepted Answer

Plant cell

Tour of the Cell: Structure and Function in General Biology

Guida di studio - Domande di pratica

Study guide - Flashcard