The basic unit of DNA structure is the
A) nitrogenous base.
B) purine.
C) pyrimidine.
D) nucleotide
Ans: D) nucleotide
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The first identification test performed on a clinical isolate of gram-positive, catalase-positive cocci would likely be the:
a. penicillin test. b. Gram stain. c. oxidase test. d. coagulase test.
The eukaryotic chromosome is composed of ____
a. DNA only b. RNA only c. DNA and carbohydrate d. DNA and protein e. RNA and protein
Which of the following adaptations is a result of natural selection acting on Plasmodium? a. All of the choices
b. Infected humans are more likely to be bitten by mosquitoes than uninfected people are. c. Infected mosquitoes are more likely to feed several times a night than uninfected mosquitoes are. d. Plasmodium has developed resistance to several antimalarial drugs.
Choose the letter of the best match from the following:A. abscisic acidB. trichomesC. aquaporinD. endodermisE. stomaPore in plasma membrane that allows water movement.
Fill in the blank(s) with the appropriate word(s).