Which microscope shows cells against a bright background and the intracellular structures of unstained cells based on their varying densities?
A. phase-contrast
B. fluorescence
C. dark-field
D. bright-field
E. electron
Answer: A
You might also like to view...
A viticulturist wants to grow larger grapes by elongating the stems of the vines. Which specific hormone would a viticulturist apply to the plants?
A. Ethylene B. Gibberellin C. Auxin D. Abscisic acid E. Cytokinin
Which embryonic tissue is defective if an embryo
develops into a creature that cannot move and has no supportive or circulatory system? a. ectoderm b. endoderm c. mesoderm d. somatoderm e. all of these
The following statements regarding penicillin production and applications are true EXCEPT
A) Penicillin is a secondary metabolite produced by a filamentous fungus. B) Penicillin derivatives can be produced by biosynthetic or semisynthetic methods. C) Natural penicillin (penicillin G) inhibits a wide spectrum of bacteria. D) Penicillin selection method is used to enrich the auxotrophic mutations. E) -lactamases, which cause penicillin resistance, are easily transferable when they are located on plasmids.
All of the following are true about prosimians except
A. they are nocturnal. B. they are big-eyed mammals with increased visual acuity. C. they are widespread. D. only two lineages survive today.