Which naturally-occurring plant hormone has a major role in the phototropic response of plants?  

A.  auxin
B.  gibberellin
C.  abscisic acid
D.  ethylene
E.  2, 4-D


A.  auxin

Biology & Microbiology

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Which of the following are components of a phospholipid?

a. a molecule of glycerol b. a phosphate molecule c. two fatty acid chains d. all of the above

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A man with the autosomal recessive disorder phenylketonuria (PKU) and a woman without PKU have a son named Peter, who does not have PKU. Peter is curious about whether his mother is a carrier for PKU. Which of the following facts would allow him to know?

What will be an ideal response?

Biology & Microbiology

The formation of carbonic acid in the oceans directly results in

A) increased sea surface temperatures. B) inhibition of shell growth in marine animals. C) increased marine biodiversity. D) increased pH.

Biology & Microbiology

The Carboniferous Period is known for

A. the appearance of the first true mammals. B. the first examples of terrestrial gymnosperms. C. the appearance of the first angiosperms. D. the formation of rich coal deposits. E. a rapid increase in the diversity of marine invertebrates.

Biology & Microbiology