The current mass extinction is believed to be primarily caused by
a) human actions
b) rising sea levels
c) plate tectonics
d) asteroid impact
e) reduction in the amount of oxygen in the atmosphere
Answer: a) human actions
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Amino acids are linked together by peptide bonds in a ____
A. starch. B. polypeptide. C. polysaccharide. D. nucleic acid. E. phospholipid.
If complementary DNA strands were arranged in a parallel manner, what would you expect to see?
A) Complementary nucleotides would be attracted to each other, forming ionic bonds that would make the helix stable but not uniform in width. B) Charges of complementary nucleotides would repel and no hydrogen bonds would form. C) Complementary nucleotides would line up properly; but fewer hydrogen bonds would form, so the strands could be more easily pulled apart. D) Purines would pair with both purines and pyrimidines due to the closer alignment of the parallel strands. E) There would be no discernable difference between DNA strands aligned in a parallel versus an antiparallel manner.
Specialized symbiotic associations between the roots of plants and fungi are called
A. a mycelial unit. B. heterokaryotic junctions. C. lichens. D. hyphal associations. E. mycorrhizae.
The relationship between strands of RNA and DNA during transcription is ______________.
A. antagonistic B. opposite C. complementary D. an exact duplicate E. unrelated