Unit 2: Microscopes

Question 1

A cell is treated with a toxin that prevents the synthesis of new lysosomes. However, the cell continues to produce the hydrolytic enzymes normally found in lysosomes.

In which structure are the hydrolytic enzymes most likely to accumulate?

Answer 1

Lysosomes are synthesized by the Golgi complex

if they aren’t synthesized, this is where they will accumulate.

Question 2

A cytologist uses a microscope to compare a human hepatocyte and a human epithelial cell. She observes that the smooth endoplasmic reticulum (ER) of the hepatocyte is larger and contains more folds than the smooth ER of the epithelial cell.

What does this tell you about lipids synthesis?

Answer 2

The hepatocyte is able to synthesize lipids more efficiently than the epithelial cell.

Question 3

Chlorophyll a is a pigment that absorbs light energy from the sun and gives plants their green color.

Which plant cell structure is most likely to contain chlorophyll a?

Answer 3

Chloroplast

Question 4

Which is the smallest biological structure that would most likely be visible with a standard research-grade light microscope?

Answer 4

chloroplast

Question 5

Which microscopy techniques is best suited for visualizing protein complexes in their cellular environments without the use of preservatives?

Answer 5

cryo-electron microscopy

Question 6

What is a major advantage of light microscopy over electron microscopy?

Answer 6

light microscopy allows the visualization of dynamic processes in living cells

Question 7

If homogenized cells are fractionated by differential centrifugation, which organelles will require the greatest centrifugation speed to form a pellet at the bottom of the tube?

Answer 7

ribosomes

Question 8

Why can a modern transmission electron microscope (TEM) achieve a resolution of about 2.0 nanometers, whereas a standard light microscope has a maximum resolution of about 200 nanometers?

Answer 8

The wavelengths of electron beams are much shorter than the wavelengths of visible light.

Question 9

Which of the following is the most appropriate technique for observing the movements of condensed chromosomes during cell division?

Answer 9

standard light microscopy

Question 10

Which is the most appropriate technique for observing and measuring the size of ribosomes in a eukaryotic cell?

Answer 10

transmission electron microscopy

Question 11

Which is the most appropriate technique for observing the three-dimensional structure and organization of microvilli on an intestinal cell?

Answer 11

scanning electron microscopy