BIOD102 FINAL 2026 TEST PAPER SOLVED
QUESTIONS AND SOLUTIONS
◉ Deletion mutation. Answer: Occurs from the loss of nucleotides
within a gene
◉ Nonsense mutation. Answer: Occurs when a point mutation turns
the intended codon into a 'stop' codon
◉ Missense mutation. Answer: Occurs when one amino acid is
replaced with another.
◉ Point mutations. Answer: Occurs when a single nucleotide is
changed within a gene
◉ Describe the two phases of the cell cycle.. Answer: Interphase and
mitotic phase... interphase consists of G1, S, and G2 phases. G1 and
G2 are the gap phases that are characterized by cell growth, such as
protein and organelle production. S-phase (synthesis) is the time
during which chromosomes are duplicated and essential DNA
information is replicated to be passed to daughter cells during
mitosis. Mitosis is the division of genetic material and can be broken
,down into 5 subphases... prophase, metaphase, prometaphase,
anaphase and telophase.
◉ Origin of replication. Answer: Encodes for a start signal at which
the process of replication will be initiated by proteins that recognize
and bind to those sequences.
◉ Topoisomerase. Answer: Breaks the hyDrogen bonds of the
nucleotide bases.
◉ Helicase. Answer: Untwists and she role of untwisting and
separating the helix parent strands at the replication form
◉ Replication fork. Answer: Y Shaped area where the DNA strands
are beginning to untwist
◉ What are DNA polymerases?. Answer: DNA polymerase is an
enzyme that adds nucleotides to the 3' end of the existing chain via
dehydration reactions.
◉ Mismatch repair. Answer: Occurs when other proteins identify
inappropriately mismatched nucleotides and replace them with the
correct nucleotide.
,◉ Nucleotide excision repair. Answer: Deployed when entire
stretches of newly synthesized stand is erroneous. The cell deploys
the mechanism and nucleases will cleave out a short stretch of DNA
on the new star and tend the template strand will again be used to
determine the correct complementary pairs to fill the gap.
◉ How do telomeres shorten degradation of the 5' ends of DNA?.
Answer: Telomeres are specialized nucleotide sequences that serve
as a protective tail on the ends of strands. Telomeres can be thought
of as placeholders, namely, short, repeating sequences that do not
hold any relevant genetic information.
◉ The process by which genes are expressed that encode for
proteins occurs in two steps called..... Answer: Transcription and
translation
◉ What type of RNA contains the exact sequence of DNA and
dictates "how" to build a protein?. Answer: MRNA
◉ What ar the tree stages of transcription?. Answer: Initiation,
elongation, termination
◉ Which stage of transcription involves the polyadenylation
sequence?. Answer: Termination
, ◉ Three modifications that can be made to pre-mRNA for it to be
considered functional mature mRNA. Answer: 1. 5' cap - guanine
nucleotide that has been modified by the attachement of
phosphates.
2. Poly-A-Tail - seres of 50-250 adenine nucleotides that modifies the
3' end
3. RNA splicing - final modification of pre-mRNA that occurs within
the nucleus
◉ Introns. Answer: Noncoding regions of DNA that are removed
during RNA splicing
◉ Main role of tRNA. Answer: Transferring available amino acids
from the cytosol to the growing polypeptide chain
◉ Small subunit of a ribosome has a binding site for.... Answer:
MRNA
◉ Which stage of translation involves binding of the small ribosomal
unit with mature mRNA?. Answer: Initiation
◉ How do acetylation and methylation act as an "on"/"off" switch
for transcription?. Answer: Acetylation - addition of acetyl groups to
an amino acid of the histone (within chromatin) tail, flops the switch
"on", inducing transcription. Methylation, which is the addition of
QUESTIONS AND SOLUTIONS
◉ Deletion mutation. Answer: Occurs from the loss of nucleotides
within a gene
◉ Nonsense mutation. Answer: Occurs when a point mutation turns
the intended codon into a 'stop' codon
◉ Missense mutation. Answer: Occurs when one amino acid is
replaced with another.
◉ Point mutations. Answer: Occurs when a single nucleotide is
changed within a gene
◉ Describe the two phases of the cell cycle.. Answer: Interphase and
mitotic phase... interphase consists of G1, S, and G2 phases. G1 and
G2 are the gap phases that are characterized by cell growth, such as
protein and organelle production. S-phase (synthesis) is the time
during which chromosomes are duplicated and essential DNA
information is replicated to be passed to daughter cells during
mitosis. Mitosis is the division of genetic material and can be broken
,down into 5 subphases... prophase, metaphase, prometaphase,
anaphase and telophase.
◉ Origin of replication. Answer: Encodes for a start signal at which
the process of replication will be initiated by proteins that recognize
and bind to those sequences.
◉ Topoisomerase. Answer: Breaks the hyDrogen bonds of the
nucleotide bases.
◉ Helicase. Answer: Untwists and she role of untwisting and
separating the helix parent strands at the replication form
◉ Replication fork. Answer: Y Shaped area where the DNA strands
are beginning to untwist
◉ What are DNA polymerases?. Answer: DNA polymerase is an
enzyme that adds nucleotides to the 3' end of the existing chain via
dehydration reactions.
◉ Mismatch repair. Answer: Occurs when other proteins identify
inappropriately mismatched nucleotides and replace them with the
correct nucleotide.
,◉ Nucleotide excision repair. Answer: Deployed when entire
stretches of newly synthesized stand is erroneous. The cell deploys
the mechanism and nucleases will cleave out a short stretch of DNA
on the new star and tend the template strand will again be used to
determine the correct complementary pairs to fill the gap.
◉ How do telomeres shorten degradation of the 5' ends of DNA?.
Answer: Telomeres are specialized nucleotide sequences that serve
as a protective tail on the ends of strands. Telomeres can be thought
of as placeholders, namely, short, repeating sequences that do not
hold any relevant genetic information.
◉ The process by which genes are expressed that encode for
proteins occurs in two steps called..... Answer: Transcription and
translation
◉ What type of RNA contains the exact sequence of DNA and
dictates "how" to build a protein?. Answer: MRNA
◉ What ar the tree stages of transcription?. Answer: Initiation,
elongation, termination
◉ Which stage of transcription involves the polyadenylation
sequence?. Answer: Termination
, ◉ Three modifications that can be made to pre-mRNA for it to be
considered functional mature mRNA. Answer: 1. 5' cap - guanine
nucleotide that has been modified by the attachement of
phosphates.
2. Poly-A-Tail - seres of 50-250 adenine nucleotides that modifies the
3' end
3. RNA splicing - final modification of pre-mRNA that occurs within
the nucleus
◉ Introns. Answer: Noncoding regions of DNA that are removed
during RNA splicing
◉ Main role of tRNA. Answer: Transferring available amino acids
from the cytosol to the growing polypeptide chain
◉ Small subunit of a ribosome has a binding site for.... Answer:
MRNA
◉ Which stage of translation involves binding of the small ribosomal
unit with mature mRNA?. Answer: Initiation
◉ How do acetylation and methylation act as an "on"/"off" switch
for transcription?. Answer: Acetylation - addition of acetyl groups to
an amino acid of the histone (within chromatin) tail, flops the switch
"on", inducing transcription. Methylation, which is the addition of
