BIO 105 EXAM 4 CORE BODY SYSTEMS AND
HOMEOSTASIS REVIEW 2026
◉ All of the following are true about the structure of
deoxyribonucleic acid except __________.
1. a single nucleotide has a phosphate group, pentose sugar, and
nitrogenous base. The primary structure of DNA consists of
nitrogenous bases sticking out from the backbone
2. nucleotides consist of a phosphate group, pentose sugar, and
nitrogenous base. The primary structure of DNA has a sugar-
phosphate backbone
3. phosphodiester bonds connect deoxyribonucelotides in the
primary structure of DNA
4. deoxyribonucleotides consist of a nitrogenous base and a pentose
sugar with the nitrogenous bases covalently bonded to make the
primary structure
5. complementary base pairing between the nitrogenous bases from
two strands of nucleotides forms the secondary structure of DNA.
Answer: 4. deoxyribonucleotides consist of a nitrogenous base and a
pentose sugar with the nitrogenous bases covalently bonded to
make the primary structure
◉ DNA is synthesized through a process known as _____.
,1. conservative replication
2. translation
3. transcription
4. semiconservative replication.
Answer: 4. semiconservative replication
◉ Semiconservative replication involves a template. What is the
template?
1. an RNA molecule
2. single-stranded binding proteins
3. DNA polymerase
4. one strand of the DNA molecule.
Answer: 4. one strand of the DNA molecule
◉ Which of the following help(s) to hold the DNA strands apart
while they are being replicated?
1. nuclease
2. primase
3. ligase
, 4. single-strand DNA binding proteins
5. DNA polymerase.
Answer: 4. single-stranded DNA binding proteins
◉ What is the role of DNA ligase in the elongation of the lagging
strand during DNA replication?
1. It unwinds the parental double helix.
2. It synthesizes RNA nucleotides to make a primer.
3. It joins Okazaki fragments together.
4. It stabilizes the unwound parental DNA.
5. It catalyzes the lengthening of telomeres..
Answer: 3. It joins Okazaki fragments together
◉ The leading and the lagging strands differ in that _____.
1. the leading strand is synthesized by adding nucleotides to the 3'
end of the growing strand, and the lagging strand is synthesized by
adding nucleotides to the 5' end
2. the lagging strand is synthesized continuously, whereas the
leading strand is synthesized in short fragments that are ultimately
stitched together
3. the leading strand is synthesized at twice the rate of the lagging
strand
HOMEOSTASIS REVIEW 2026
◉ All of the following are true about the structure of
deoxyribonucleic acid except __________.
1. a single nucleotide has a phosphate group, pentose sugar, and
nitrogenous base. The primary structure of DNA consists of
nitrogenous bases sticking out from the backbone
2. nucleotides consist of a phosphate group, pentose sugar, and
nitrogenous base. The primary structure of DNA has a sugar-
phosphate backbone
3. phosphodiester bonds connect deoxyribonucelotides in the
primary structure of DNA
4. deoxyribonucleotides consist of a nitrogenous base and a pentose
sugar with the nitrogenous bases covalently bonded to make the
primary structure
5. complementary base pairing between the nitrogenous bases from
two strands of nucleotides forms the secondary structure of DNA.
Answer: 4. deoxyribonucleotides consist of a nitrogenous base and a
pentose sugar with the nitrogenous bases covalently bonded to
make the primary structure
◉ DNA is synthesized through a process known as _____.
,1. conservative replication
2. translation
3. transcription
4. semiconservative replication.
Answer: 4. semiconservative replication
◉ Semiconservative replication involves a template. What is the
template?
1. an RNA molecule
2. single-stranded binding proteins
3. DNA polymerase
4. one strand of the DNA molecule.
Answer: 4. one strand of the DNA molecule
◉ Which of the following help(s) to hold the DNA strands apart
while they are being replicated?
1. nuclease
2. primase
3. ligase
, 4. single-strand DNA binding proteins
5. DNA polymerase.
Answer: 4. single-stranded DNA binding proteins
◉ What is the role of DNA ligase in the elongation of the lagging
strand during DNA replication?
1. It unwinds the parental double helix.
2. It synthesizes RNA nucleotides to make a primer.
3. It joins Okazaki fragments together.
4. It stabilizes the unwound parental DNA.
5. It catalyzes the lengthening of telomeres..
Answer: 3. It joins Okazaki fragments together
◉ The leading and the lagging strands differ in that _____.
1. the leading strand is synthesized by adding nucleotides to the 3'
end of the growing strand, and the lagging strand is synthesized by
adding nucleotides to the 5' end
2. the lagging strand is synthesized continuously, whereas the
leading strand is synthesized in short fragments that are ultimately
stitched together
3. the leading strand is synthesized at twice the rate of the lagging
strand
