Molecular Biology Test Questions
and answers graded A+
DNA and RNA are polymers called_, and are made of monomers called __ - ANS✅✅nucleic acids;
amino acids
What are the three parts of a nucleotide? - ANS✅✅nitrogen base, phosphate group, sugar
What does the pentagon, indicated by the number 1 on the figure, represent? - ANS✅✅sugar
What does the circle, indicated by the number 2 on the figure, represent? - ANS✅✅phosphate
What do the numbers 3 and 4 on the figure represent? - ANS✅✅nitrogen base
What type of sugar is found in DNA? - ANS✅✅deoxyribose
What are the four nitrogen bases in DNA? - ANS✅✅adenine, guanine, cytosine, thymine
How do the bases pair in DNA? - ANS✅✅adenine and thymine; cytosine and guanine
What scientist discovered the base pairing rules? - ANS✅✅chargaff
List the three ways that RNA is different from DNA. - ANS✅✅1. In DNA, the sugar is deoxyribose
and in RNA the sugar is ribose.
2. In RNA, thymine is changed from thymine to uracil.
3. RNA is usually single stranded unlike DNA which is a double helix.
If the DNA double helix were a twisted ladder, what would the sides of the ladder be made of? -
ANS✅✅sugar and phosphate
What type of bonds hold together the sides of the DNA molecule? - ANS✅✅covalent
, What would the rungs of the ladder be made of? - ANS✅✅4 Nitrogen bases- adenine, thymine,
cytosine, guanine
What type of bonds hold together the rungs of the DNA molecule? - ANS✅✅hydrogen
Who discovered the structure of DNA? - ANS✅✅watson and crick
What term did the scientists Watson and Crick give to the structure of the DNA molecule? -
ANS✅✅double-helix
A _____ is a segment of DNA that codes for a protein. - ANS✅✅gene
For DNA to code for protein, the genetic code must first be converted into _______ by the process
of______. - ANS✅✅RNA, transcription
Where does the process transcription take place? - ANS✅✅nucleus
Describe what happens in transcription. - ANS✅✅DNA nucleotides are changed to RNA
nucleotides
1. Helicase unwinds and unzips DNA.
2. RNA polymerase reads the DNA strand and attaches the complementary mRNA nucleotide.
3. mRNA breaks off and leaves the nucleus to go to the ribosome for protein synthesis.
4. DNA strands rejoin.
mRNA EDITING
*Before mRNA leaves the nucleus, introns are removed and exons are spliced together
introns- sequences of nucleotides in a gene that do not code for a protein
exon- DNA sequences that code for proteins
The first step of this process is to unzip the DNA molecule. What molecule does this? -
ANS✅✅helicase
mRNA codes for proteins in a process called ____. - ANS✅✅translation
and answers graded A+
DNA and RNA are polymers called_, and are made of monomers called __ - ANS✅✅nucleic acids;
amino acids
What are the three parts of a nucleotide? - ANS✅✅nitrogen base, phosphate group, sugar
What does the pentagon, indicated by the number 1 on the figure, represent? - ANS✅✅sugar
What does the circle, indicated by the number 2 on the figure, represent? - ANS✅✅phosphate
What do the numbers 3 and 4 on the figure represent? - ANS✅✅nitrogen base
What type of sugar is found in DNA? - ANS✅✅deoxyribose
What are the four nitrogen bases in DNA? - ANS✅✅adenine, guanine, cytosine, thymine
How do the bases pair in DNA? - ANS✅✅adenine and thymine; cytosine and guanine
What scientist discovered the base pairing rules? - ANS✅✅chargaff
List the three ways that RNA is different from DNA. - ANS✅✅1. In DNA, the sugar is deoxyribose
and in RNA the sugar is ribose.
2. In RNA, thymine is changed from thymine to uracil.
3. RNA is usually single stranded unlike DNA which is a double helix.
If the DNA double helix were a twisted ladder, what would the sides of the ladder be made of? -
ANS✅✅sugar and phosphate
What type of bonds hold together the sides of the DNA molecule? - ANS✅✅covalent
, What would the rungs of the ladder be made of? - ANS✅✅4 Nitrogen bases- adenine, thymine,
cytosine, guanine
What type of bonds hold together the rungs of the DNA molecule? - ANS✅✅hydrogen
Who discovered the structure of DNA? - ANS✅✅watson and crick
What term did the scientists Watson and Crick give to the structure of the DNA molecule? -
ANS✅✅double-helix
A _____ is a segment of DNA that codes for a protein. - ANS✅✅gene
For DNA to code for protein, the genetic code must first be converted into _______ by the process
of______. - ANS✅✅RNA, transcription
Where does the process transcription take place? - ANS✅✅nucleus
Describe what happens in transcription. - ANS✅✅DNA nucleotides are changed to RNA
nucleotides
1. Helicase unwinds and unzips DNA.
2. RNA polymerase reads the DNA strand and attaches the complementary mRNA nucleotide.
3. mRNA breaks off and leaves the nucleus to go to the ribosome for protein synthesis.
4. DNA strands rejoin.
mRNA EDITING
*Before mRNA leaves the nucleus, introns are removed and exons are spliced together
introns- sequences of nucleotides in a gene that do not code for a protein
exon- DNA sequences that code for proteins
The first step of this process is to unzip the DNA molecule. What molecule does this? -
ANS✅✅helicase
mRNA codes for proteins in a process called ____. - ANS✅✅translation
