BSC 108 EXAM 3 - UNIVERSITY OF
ALABAMA QUESTIONS AND ANSWERS.
VERIFIED 2025/2026.
What is the structure of a strand of DNA? - ANS double helix, twisted ladder
What is DNA composed of? - ANS nucleotide subunits
What is the backbone of DNA? - ANS deoxyribose and a phosphate group
What is the backbone of DNA covalently bonded to? - ANS nitrogen-containing bases
How many strands of DNA does a DNA molecule contain? - ANS two
The two strands of DNA are: - ANS complementary
What are the nitrogen-containing bases in DNA? - ANS adenine, guanine, thymine, cytosine
How are the nitrogen-containing bases held together? - ANS hydrogen bonds
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,What bases pair together? - ANS adenine=thymine
guanine=cytosine
How does DNA replicate? - ANS DNA molecule unwinds and each strand is a template for
complementary base pairing; each daughter helix contains an intact strand from the parent
helix and a newly synthesized strand therefore DNA replication is semiconservative
One parent molecule is composed of two __________________ that separate. -
ANS complementary strands
Each strand is used as a ______________ to make a new strand. - ANS template
What are the two daughter molecules composed of? - ANS One "old" (parent) strand and
one "new" (synthesized) strand
Where do parent strands separate? - ANS origins of replication
Where and how does synthesis of two new complementary strands occur? - ANS replication
bubbles, using the parent strands as templates
What do the replication bubbles do as DNA replication progresses in both directions at the
replication forks? - ANS merge
How does an organism's DNA lead to specific traits? - ANS by dictating the synthesis of
proteins
What is the structure of RNA? - ANS single-stranded nucleic acid
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, RNA contains ________ instead of thymine. - ANS Uracil
What sugar is used in RNA? - ANS ribose
What is the function of mRNA (messenger RNA)? - ANS carries the genetic message from a
gene (DNA) to ribosomes that translate it into a protein
What is the function of tRNA (transfer RNA)? - ANS translates codons into amino acids
Where does tRNA pair with mRNA? - ANS at the anitcodon
What is the function of rRNA (ribosomal RNA)? - ANS to make up ribosomes with proteins
What two processes do genes code for specific proteins? - ANS transcription and translation
What is transcription? - ANS synthesis of mRNA under the direction of DNA
Where does transcription occur? - ANS nucleus of a cell
What is translation? - ANS synthesis of a polypeptide (which will become a protein) under the
direction of mRNA
Where does translation occur? - ANS on the ribosomes in the cytoplasm
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
ALABAMA QUESTIONS AND ANSWERS.
VERIFIED 2025/2026.
What is the structure of a strand of DNA? - ANS double helix, twisted ladder
What is DNA composed of? - ANS nucleotide subunits
What is the backbone of DNA? - ANS deoxyribose and a phosphate group
What is the backbone of DNA covalently bonded to? - ANS nitrogen-containing bases
How many strands of DNA does a DNA molecule contain? - ANS two
The two strands of DNA are: - ANS complementary
What are the nitrogen-containing bases in DNA? - ANS adenine, guanine, thymine, cytosine
How are the nitrogen-containing bases held together? - ANS hydrogen bonds
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,What bases pair together? - ANS adenine=thymine
guanine=cytosine
How does DNA replicate? - ANS DNA molecule unwinds and each strand is a template for
complementary base pairing; each daughter helix contains an intact strand from the parent
helix and a newly synthesized strand therefore DNA replication is semiconservative
One parent molecule is composed of two __________________ that separate. -
ANS complementary strands
Each strand is used as a ______________ to make a new strand. - ANS template
What are the two daughter molecules composed of? - ANS One "old" (parent) strand and
one "new" (synthesized) strand
Where do parent strands separate? - ANS origins of replication
Where and how does synthesis of two new complementary strands occur? - ANS replication
bubbles, using the parent strands as templates
What do the replication bubbles do as DNA replication progresses in both directions at the
replication forks? - ANS merge
How does an organism's DNA lead to specific traits? - ANS by dictating the synthesis of
proteins
What is the structure of RNA? - ANS single-stranded nucleic acid
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, RNA contains ________ instead of thymine. - ANS Uracil
What sugar is used in RNA? - ANS ribose
What is the function of mRNA (messenger RNA)? - ANS carries the genetic message from a
gene (DNA) to ribosomes that translate it into a protein
What is the function of tRNA (transfer RNA)? - ANS translates codons into amino acids
Where does tRNA pair with mRNA? - ANS at the anitcodon
What is the function of rRNA (ribosomal RNA)? - ANS to make up ribosomes with proteins
What two processes do genes code for specific proteins? - ANS transcription and translation
What is transcription? - ANS synthesis of mRNA under the direction of DNA
Where does transcription occur? - ANS nucleus of a cell
What is translation? - ANS synthesis of a polypeptide (which will become a protein) under the
direction of mRNA
Where does translation occur? - ANS on the ribosomes in the cytoplasm
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
