Chapter 4

The ultrastructure of a chloroplast is best studied using a a. light microscope. b. scanning electron microscope. c. transmission electron microscope. d. light microscope and fluorescent dyes.

The cells of an ant and an elephant are, on average, the same small size; an elephant just has more of them. What is the main advantage of small cell size? (Explain your reasoning.) a. A small cell has a larger plasma membrane surface area than does a large cell. b. Small cells can better take up sufficient nutrients and oxygen to service their cell volume. c. It takes less energy to make an organism out of small cells. d. Small cells require less oxygen than do large cells.

Which of the following clues would tell you whether a cell is prokaryotic or eukaryotic? a. the presence or absence of a rigid cell wall b. whether or not the cell is partitioned by internal membranes c. the presence or absence of ribosomes d. Both \(\mathrm{b}\) and \(\mathrm{c}\) are important clues.

Which of the following is one of the major components of the plasma membrane of a plant cell? a. phospholipids b. cellulose fibers c. collagen fibers d. pectins

What four cellular components are shared by prokaryotic and eukaryotic cells?

Describe two different ways in which cilia can function in organisms.

Choose from the following cells : a. pancreatic cell that secretes digestive enzymes b. ovarian cell that produces estrogen (a steroid hormone) c. muscle cell in the thigh of a long-distance runner d. white blood cell that engulfs bacteria In which cell would vou find the most lysosomes?

Choose from the following cells : a. pancreatic cell that secretes digestive enzymes b. ovarian cell that produces estrogen (a steroid hormone) c. muscle cell in the thigh of a long-distance runner d. white blood cell that engulfs bacteria In which cell would you find the most smooth ER?

Choose from the following cells : a. pancreatic cell that secretes digestive enzymes b. ovarian cell that produces estrogen (a steroid hormone) c. muscle cell in the thigh of a long-distance runner d. white blood cell that engulfs bacteria In which cell would you find the most rough ER?

In what ways do the internal membranes of a eukaryotic cell contribute to the functioning of the cell?

Describe the structure of the plasma membrane of an animal cell. What would be found directly inside and outside the membrane?

Imagine a spherical cell with a radius of \(10 \mu \mathrm{m}\). What is the cell's surface area in \(\mu \mathrm{m}^{2}\) ? Its volume, in \(\mu \mathrm{m}^{3}\) ? (Note: For a sphere of radius \(r,\) surface area \(=4 \pi r^{2}\) and volume \(=4 / 3 \pi r^{3}\). Remember that the value of \(\pi\) is \(3.14 .\) ) What is the ratio of surface area to volume for this cell? Now do the same calculations for a second cell, this one with a radius of \(20 \mu \mathrm{m}\). Compare the surface-to-volume ratios of the two cells. How is this comparison significant to the functioning of cells?

How might the phrase "ingested but not digested" be used in a description of the endosymbiotic theory?