Which one of the following statements about DNA structure is not true? a) The tw
ID: 270259 • Letter: W
Question
Which one of the following statements about DNA structure is not true?
a)
The two DNA strands are held together by covalent bonds between complementary bases.
b)
DNA exists as a double-stranded helix.
c)
The strands in the helix are antiparallel to one another.
d)
The phosphate-sugar backbone is located on the outside of the helix.
Question 6 (2 points)
Which one of the following statements does not describe an aspect of translation?
a)
Translation takes place in the cytoplasm.
b)
Incoming tRNA molecules carrying the next amino acid in the protein bind to the P site on the ribosome.
c)
Energy (i.e. ATP) is required to synthesize a protein during translation.
d)
Ribosomes, the sites of translation, are composed of ribosomal RNA (rRNA) and proteins.
Question 7 (2 points)
In a messenger RNA molecule where cytosine (C) makes up 20% of the total bases, what can you tell about the percentages of the other bases present?
a)
Contains 20% guanine (G) bases
b)
Contains 20% uracil (U) bases
c)
Contains 30% adenine (A) bases
d)
Both (a) and (c)
e)
Cannot determine the complete base composition of this mRNA
Question 8 (2 points)
Which one of the following statements does not describe the process of transcription?
a)
mRNA is sythesized from its 5' end to its 3' end.
b)
Transcription takes place in the nucleus.
c)
The synthesized RNA strand is identical to the DNA template strand.
d)
At the beginning of the transcription process, RNA polymerase binds to a promoter/control segment in the DNA.
Explanation / Answer
5. A. The two DNA strands are held together by covalent bonds between complementary bases.
The two strands of DNA are held by Hydrogen bonds formed between nitrogen bases on opposite strands and not by covalent bonds.
6. B. Incoming tRNA molecules carrying the next amino acid in the protein bind to the P site on the ribosome.
Ribosome has three sites A site, P site and E site. The incoming tRNA molecule carrying amino acid binds to A site on the ribosome.
7. A. Contains 20% guanine (G) bases.
According to Charguff rule, amount of Adenine is equal to amount of thymine and amount of cytosine is equal to amount of Guanine.
8. C. The synthesized RNA strand is identical to the DNA template strand.
The synthesized RNA is identical to non template strand or coding strand except that thymine in DNA strand is replaced by uracil in RNA .
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.