Question 1

Which type of microscopy is best suited for viewing the surface details of a specimen in three dimensions at relatively low magnification (20-80x)?

Accepted Answer

Dissecting (stereo) microscope

Question 2

What is the main advantage of phase contrast microscopy over standard bright field microscopy when observing living, unstained cells?

Accepted Answer

It amplifies differences in phase of light, increasing contrast of denser structures.

Question 3

Which property of a microscope determines its ability to distinguish two adjacent structures as separate entities?

Accepted Answer

Resolution

Question 4

A scientist wants to study the internal structure of mitochondria at very high resolution. Which microscopy technique should they use?

Accepted Answer

Transmission electron microscopy (TEM)

Question 5

Why are cells generally small rather than large, according to the surface area-to-volume ratio?

Accepted Answer

Smaller cells have a higher surface area-to-volume ratio, allowing for more efficient exchange of materials.

Question 6

Which structure is found in both prokaryotic and eukaryotic cells and is responsible for protein synthesis?

Accepted Answer

Ribosome

Question 7

Gram-positive bacteria differ from gram-negative bacteria in which of the following ways?

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan cell wall and teichoic acids.

Question 8

Which process of horizontal gene transfer involves the uptake of naked DNA from the environment by a bacterial cell?

Accepted Answer

Transformation

Question 9

Endosymbiotic theory explains the origin of which two eukaryotic organelles?

Accepted Answer

Mitochondria and chloroplasts

Question 10

Which evidence supports the endosymbiotic theory for the origin of mitochondria and chloroplasts?

Accepted Answer

They contain their own circular DNA and ribosomes similar to bacteria.

Question 11

A cell is observed to have a large number of rough endoplasmic reticulum and Golgi apparatus. What is the most likely function of this cell?

Accepted Answer

Protein secretion

Question 12

Which organelle is responsible for breaking down macromolecules using hydrolytic enzymes at low pH?

Accepted Answer

Lysosome

Question 13

Which cytoskeletal element is primarily responsible for maintaining cell shape and providing tracks for organelle movement?

Accepted Answer

Microtubules

Question 14

What is the correct sequence for the pathway of protein synthesis from DNA to secretion in a eukaryotic cell?

Accepted Answer

DNA → mRNA → ribosome (RER) → Golgi apparatus → vesicle → plasma membrane

Question 15

Which cell junction allows for the direct passage of small molecules and ions between adjacent animal cells, facilitating communication?

Accepted Answer

Gap junction

Question 16

Which of the following is NOT a feature of prokaryotic cells?

Accepted Answer

Membrane-bound organelles

Question 17

A bacterial cell is exposed to extreme heat and nutrient deprivation. Which structure allows it to survive these harsh conditions for centuries?

Accepted Answer

Endospore

Question 18

Which organelle is found in plant cells but not in animal cells and is responsible for photosynthesis?

Accepted Answer

Chloroplast

Question 19

If a cell has a large number of contractile vacuoles, what environment is it most likely adapted to?

Accepted Answer

Freshwater environment

Question 20

Which formula correctly calculates the surface area of a cube-shaped cell with width $$w$$?

Accepted Answer

$$6w^2$$

A Tour of the Cell: Microscopy and Cell Structure

Study Guide - Practice Questions