Principles of Biology Ch. 4

Which technique is used to separate different part of cells so that they can be studied by both physical and chemical methods?

Cell fractionation

The smooth ER is the primary site for the synthesis of proteins and cholesterol needed to make membranes.

False

The many short appendages that a cell has are called cilia.

True

The micrometer (μm) is the most convenient unit for measuring cells.

True

What type of microscopy uses a laser to excite fluorophores in a thin "slice" through a cell?

a. confocal microscopy

The ratio of the size of the image seen with the microscope to the actual size of the object is called:

a. magnification

5. A cell is surrounded by which distinctive surface membrane?

a. plasma membrane

Evidence that all living cells have a common origin is best illustrated by

a. the basic similarities in cell structure and chemistry

Almost every vertebrate cell has a primary cilium, a single cilium on the cell surface that serves as a cellular antenna.

b. False

Enzymes called proteases in the ER lumen catalyze folding of proteins into proper conformations.

b. False

Peroxisomes are found in large numbers in cells that synthesize, store, and degrade lipids, and one of their functions is to break down protein molecules.

b. False

4. The accompanying image is the product of which type of microscope?

b. Nomarski differential interference microscope

Plants lack organ systems for disposing of toxic metabolic waste products. Their cells' vacuoles are similar to which animal cell organelle?

b. lysosomes

The smooth ER is the primary site for the synthesis of phospholipids and cholesterol needed to make ____.

e. cell membranes

What enzyme in the ER lumen catalyzes the efficient folding of proteins into proper conformations?

e. molecular chaperones

What is a characteristic found in both prokaryotic and eukaryotic cells?

e. plasma membrane

Which two organelles are responsible for converting energy into forms that can be used by cells?

mitochondria and chloroplasts

In scanning electron microscopy, an electron beam passes through a very thin slice of a specimen and then falls onto a photographic plate or a fluorescent screen.

False

If a bacterial toxin destroys ribosomes, what cellular activity will be affected first?

a. Protein synthesis

Microfilaments are linked with one another and with other proteins by linker proteins.

a. True

Specialized structures within a living cell are known as

a. organelles.

18. Upon observing a cell of a grass blade, you notice a prominent sac that occupies a large portion of the cell. Which organelle is this?

b. vacuole

Which strategy is the most effective for larger cells to have an effective surface area to volume ratio?

c. having thin, finger-like projections

What does the nucleolus, within the nucleus, synthesize?

d. ribosomal RNA

A basal body anchors what part of a cell?

flagellum

Intermediate filaments are most closely associated with which of the following?

keratins

What is the primary function of mitochondria?

transformation of energy

What is the purpose of the cristae of the inner membrane of mitochondria?

To increase surface area

Which of the following organelles plays an important role in apoptosis, or programmed cell death?

b. mitochondria

DNA is associated with certain proteins, forming a complex called:

b. chromatin