In fish, jaws evolved from ________
a. gills
b. armor plates around the heads of placoderms
c. the spiracle
d. supporting structures for gill slits
d
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All of the following statements about digestion are correct EXCEPT:
A. Digestion is catalyzed by enzymes. B. During digestion, nucleic acids are split into nucleotides. C. During digestion, fats are split into monoglycerides and fatty acids. D. Most digestion occurs in the stomach. E. During digestion, polysaccharides and disaccharides are split into monosaccharides.
For a gene to be transcribed, the RNA polymerase has to bind to a(n) ________ sequence of nucleotides on the DNA.
A. initiator B. repressor C. elongation D. operon E. promotor
Modified leaves that protect meristematic tissue at the tips of woody plants are known as:
a. bulbs. b. bud scales. c. spines. d. tendrils. e. scale scars.
RNA is a multifaceted molecule and key component to the success of life. Which of the following statements about RNA is most accurate?
a. RNA is incapable of storing information, but it is vital in converting the information embedded in DNA to useful proteins. b. The world was most likely filled with DNA-life first, which evolved to produce RNA-life. c. There is no link between RNA and the possibility of it being a precursor to cellular life. d. It is possible that this complex molecule could have been a self-replicating system. e. RNA is an enzyme.