CH 1 WORD

B

A microtome is used to A) view microscopic organisms. B) slice thin sections of specimens. C) focus short wavelengths of light. D) manipulate tiny objects. E) dissect cellular organelles.

B

A scientist is examining motile protist. He wishes to determine their direction of movement. Which of the following microscopic techniques is least likely to be used to view these cells? A) light microscopy B) electron microscopy C) differential interference contrast microscopy D) fluorescence microscopy E) phase-contrast microscopy

a. Electron microscopy, preferably transmission electron microscopy, should be used. b. Phase contrast or differential-interference-contrast would be most helpful. c. Fluorescence microscopy is often used. d. Scanning electron microscopy should be used. e. Transmission electron microscopy will enable the pathologist to visualize the interior.

) A number of different types of microscopy exist. Each type of microscopy has advantages and disadvantages. Can you identify the microscope that would be most advantageous for the situations below? a. A cell biologist wishes to visualize the ribosomes of a cell. b. A microbiologist wishes to examine the motility of a bacterium. c. An immunologist wishes to determine if a lymphocyte possesses a certain surface protein. d. A virologist is trying to determine the three-dimensional shape of a virus. e. A pathologist is trying to examine the cytoplasm of a cell for changes that result from viral infection.

proteome

) The total protein content of the cell is called the ________.

Resolution; wavelength

) ________ is the ability to distinguish two objects that are close together as separate. In any microscope, this ability is determined by ________.

A

1 mm = ________ nm A) 1,000,000 B) 1000 C) 10 D) 1/1000 E) 1/1,000,000

Match the type of microscopy with the appropriate characteristic. A) amplifies variations in density B) light passes directly through specimen C) detects electrons deflected from the surface of the specimen D) shows specific molecules E) uses a laser to view a single plane of a specimen F) detects electrons passing through a specimen 10) brightfield 11) fluorescence 12) phase-contrast 13) confocal 14) transmission electron microscopy 15) scanning electron microscopy

10) B 11) D 12) A 13) E 14) F 15) C

D

Cell biology emerged from which of the following fields of biology? A) biochemistry B) cytology C) genetics D) biochemistry, cytology, and genetics E) cytology and biochemistry

E

Early microscopes did not allow clear visualization of cells because they were limited by A) magnification. B) number of kernels. C) resolution. D) refraction. E) both magnification and resolution.

A

Gregor Mendel was most influential in which field of biology? A) genetics B) chromatography C) biochemistry D) prokaryotic transformation E) cytology

C

Scanning electron microscopy (SEM) is especially suited to A) observing living specimens. B) examining internal cellular structure. C) creating a sense of depth. D) both observing living specimens and creating a sense of depth. E) simultaneously observing living specimens, examining internal cellular structure, and creating a sense of depth.

B

Scientists use various terms to describe conclusions reached through the scientific method. Which of the following terms conveys the least degree of certainty? A) theory B) hypothesis C) law D) both hypothesis and theory E) both theory and law

D

To which of the following do Mendel's observations relate? A) thermodynamics B) gravity C) ideal gas laws D) heredity E) diffusion

D

Which of the following biochemical techniques uses an electrical field to separate macromolecules based on their mobility through a semisolid gel? A) light microscopy. B) ultracentrifugation. C) chromatography. D) electrophoresis. E) mass spectrometry.

B

Which of the following can only be viewed by electron microscopy? A) frog eggs B) DNA C) nuclei D) mitochondria E) prokaryotes

C

Which of the following is an application of immunofluorescence microscopy? A) Visualization of the natural fluorescence of a specimen under UV light. B) Identification of specific components of the immune system. C) Identifying which organelle or cellular compartment contains a particular protein. D) Visualization of the surface structures of a specimen. E) Construction of three-dimensional images of structures smaller than 10 nm.

C

Which of the following is true of a nanometer? A) A nanometer is about the size of a common bacterial cell. B) A nanometer is one millionth of a meter. C) A nanometer is equivalent to 10 Angstroms (Å). D) The nanometer is the most common measurement used in measuring whole cells. E) None of the above.

D

Which of the following statements is false? A) All organisms consist of one or more cells. B) All cells arise from preexisting cells. C) The cell is the basic unit of structure for all organisms. D) All cells have a membrane-bound nucleus. E) Cells come in a wide variety of sizes and shapes.

C

Which of the following types of light microscopy improves the resolution of thick specimens by illuminating one plane of the specimen at a time? A) fluorescence microscopy B) phase-contrast microscopy C) confocal microscopy D) differential interference contrast microscopy E) brightfield microscopy

E

Which type of microscopy enhances and amplifies slight changes in the phase of transmitted light? A) differential interference contrast microscopy B) digital video microscopy C) fluorescence microscopy D) phase-contrast microscopy E) both differential interference contrast microscopy and phase-contrast microscopy