Question 1

Which of the following best describes the consequence of disrupting transmembrane proteins that link the extracellular matrix (ECM) to the cytoskeleton in animal cells?

Accepted Answer

Cell shape becomes unstable, motility is impaired, and signal reception is reduced due to loss of mechanical and signaling continuity.

Question 2

A patient has a genetic defect in dynein, a motor protein in cilia and flagella. Which combination of symptoms is most likely to result from this defect?

Accepted Answer

Impaired respiratory clearance and reduced sperm motility, leading to chronic lung infections and infertility.

Question 3

During mitosis, what is the effect of a drug that prevents microtubule disassembly?

Accepted Answer

Chromosomes cannot be separated to opposite poles, resulting in mitotic arrest.

Question 4

Which of the following correctly matches a cytoskeletal element with its primary function and example?

Accepted Answer

Intermediate filaments: mechanical support; example: keratin in skin cells.

Question 5

A mutation blocks transport between the endoplasmic reticulum (ER) and the Golgi apparatus. What is the most likely cellular consequence?

Accepted Answer

Secretory proteins accumulate in the ER and fail to reach their final destinations.

Question 6

Both plant and animal cells possess a plasma membrane. How do plant cells utilize this structure differently to maintain structural rigidity?

Accepted Answer

Plant cells rely on turgor pressure exerted by internal fluid against the cell wall, while animal cells lack this rigid boundary and rely on the cytoskeleton.

Question 7

A liver cell is specialized for detoxification. Which organelle would you expect to be especially abundant, and why?

Accepted Answer

Smooth Endoplasmic Reticulum, because it contains enzymes for lipid and drug metabolism.

Question 8

How did the rise of biological oxygen production alter evolutionary selective pressures on early life?

Accepted Answer

It enabled aerobic respiration, which is more efficient than anaerobic metabolism, and led to the extinction of many obligate anaerobes.

Question 9

Which metabolic strategy would a microorganism most likely use in an environment lacking oxygen but rich in nitrate?

Accepted Answer

Anaerobic respiration using nitrate as an alternative electron acceptor.

Question 10

Which statement best distinguishes bacterial transformation from conjugation?

Accepted Answer

Transformation involves uptake of free DNA from the environment, while conjugation requires direct cell-to-cell contact and transfer of plasmid DNA.

Question 11

Which evidence supports the Endosymbiotic Theory for the origin of mitochondria and chloroplasts?

Accepted Answer

They contain circular DNA and ribosomes similar to those of bacteria.

Question 12

A genetic disorder causes nonfunctional lysosomal enzymes. Which metabolic complication is most likely?

Accepted Answer

Accumulation of undigested macromolecules within cells, leading to cellular dysfunction.

Question 13

Which combination of intercellular junctions provides both mechanical strength and fluid containment in animal tissues?

Accepted Answer

Desmosomes for strength and tight junctions for fluid containment.

Question 14

How do cells adjust their plasma membrane composition to maintain fluidity in cold environments?

Accepted Answer

By increasing unsaturated fatty acids and decreasing cholesterol content.

Question 15

Which chemical property allows a molecule to passively diffuse across a pure phospholipid bilayer?

Accepted Answer

Small size and nonpolar (hydrophobic) character.

Question 16

A scientist observes that a cell's proteins are not reaching their correct organelle destinations. Which is the most likely explanation?

Accepted Answer

The proteins lack proper molecular destination tags, so they are mislocalized.

Question 17

Which of the following best describes transduction in bacteria?

Accepted Answer

Transfer of bacterial DNA from one cell to another via a bacteriophage (virus).

Question 18

Which eukaryotic system is thought to have originated from archaeal ancestors, according to the 'combination organisms' theory?

Accepted Answer

The information-processing systems (e.g., DNA replication and transcription machinery).

Question 19

Which of the following best explains why mineral surfaces were important for the abiotic assembly of early cell-like structures?

Accepted Answer

They provided catalytic surfaces that concentrated and organized organic molecules, facilitating polymerization.

Question 20

A cell is exposed to a chemical that prevents microtubule assembly. What is the most likely effect during cell division?

Accepted Answer

The mitotic spindle cannot form, so chromosomes cannot be separated.

Module 2 Study Guide – General Biology: Cell Structure, Function, and Evolution

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