Egg-laying mammals
a. have no nipples yet produce milk.
b. are commonly found in North America.
c. are hairless.
d. are confined to South America.
e. bear their young into permanent pouches.
Answer: a
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In transcription, RNA polymerase binds to a(n) _____________________ sequence near a gene, and then assembles a
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Fill in the blank(s) with the appropriate word(s).Which of the following is true about the enzyme telomerase?
a. It can re-establish telomere length. b. It is found only in adult cells. c. It is responsible for telomere shortening. d. It may speed up the aging process. e. It is expressed at low levels in cancer cells.
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extracted from Set 1 cells than does protein Y in the controls; Protein Y moves an even larger distance in the gel of the extracts from Set 2. Protein Z migrates the same distance on gels of proteins from the controls and the proteins extracted from Set 1, but it migrates a longer distance in extracts from Set 2 cells. Which protein is exposed only on the exterior of the cell? a) protein X b) protein Z c) protein Y d) protein W
Which of the following hormones increases when plants are flooded?
A. cytokinin B. auxin C. ethylene D. gibberellin E. abscisic acid