Bio 156 Exam 3 Questions & Answers (Updated 2026/2027) Already Graded
A+
What is the BASE PAIRING RULE for DNA? - (answer)A=T
C=G
What is the base pairing rule for RNA? - (answer)A=U
C=G
During the s-phase of interphase, the cell replicates its DNA using "SEMI-CONSERVATIVE REPLICATION".
Explain WHAT this means and WHY it is so important - (answer)WHAT: Way to copy DNA using master
strand as instructions on how to build the other side
-half of something is going to be conserved, half preserved
WHY: It's a very careful way to copy DNA
Explain exactly what happens during "semi-conservative DNA replication" - (answer)The cell will use
SEMI - CONSERVATIVE DNA REPLICATION to copy all
of its DNA prior to mitosis or meiosis. In this process, the original (master?) strand of DNA will be split in
half by DNA HELICASE and then DNA POLYMERASE will copy each half to produce two new and identical
DNA molecules from the original.
List 3 differences between DNA and RNA - (answer)DNA:
-double stranded
-nitrogenous bases: ATCG
-base pairing rule: A=T & C=G
-location: nucleus
RNA:
-single stranded
-nitrogenous bases: AUCG
,Bio 156 Exam 3 Questions & Answers (Updated 2026/2027) Already Graded
A+
-base pairing rule: A=U & C=G
-location: nucleus & cytoplasm
What is a chromosome? Draw a "duplicated CHROMOSOME" and LABEL all the parts
WHEN do chromosomes first appear in the cell cycle? - (answer)Chromosome: Condensed/compressed
superspooled DNA molecule
WHEN: during PROPHASE
(label parts: centromere & sister chromatids)
Describe 2 cellular events that happen during INTERPHASE
Describe 2 cellular events that happen during INTERPHASE - (answer)-Cell growth
-DNA replication
-Protein synthesis
(more specifically)...
-G1 phase = cell growth, organelles double
-S phase = synthesis of DNA, semi-conservative DNA replication
-G2 phase = protein synthesis, preparation for mitosis +++
-G0 phase = specialized cell "jobs" = secretion, muscle contraction,
Use the mRNA strand and the CODON KEY (On back) to answer the following questions;
a. describe the nucleotide sequence of the original DNA strand used to make the mRNA &
b. describe the primary structure of the protein in the gene on this DNA. - (answer)DNA TAC AAA TCT
CCA TTT GGG ACG ATT
mRNA AUG UUU AGA GGU AAA CCC UGC UAA
Protein Start●Phe● Arg●Gly● Lys●Pro●Cys● Stop
, Bio 156 Exam 3 Questions & Answers (Updated 2026/2027) Already Graded
A+
BRIEFLY describe the function/role of all these molecules in the protein synthesis "story".
adenine, thymine, cytosine, guanine ♦DNA polymerase ♦DNA unzipase/Helicase RNA polymerase
♦Messenger RNA (mRNA) ♦Ribosomal RNA (rRNA) ♦Transfer RNA (tRNA) ♦glycine or any another amino
acid ♦protein polymerase - (answer)-Adenine, thymine, cytosine, guanine: monomer nucleotides used
to form the DNA polymer.
-DNA polymerase: the enzyme that copies and repairs DNA.
-DNA unzipase/Helicase: the enzyme that separates the two sides of the DNA molecule by disrupting
the hydrogen bonds between complimentary nucleotides.
-RNA polymerase: the enzyme that copies and repairs RNA
-Messenger RNA (mRNA): the the actual copy of the DNA GENE, a nucleotide recipe for a single protein
-Ribosomal RNA (rRNA): is a strand of RNA which will form a RIBOSOME. A ribosome is a 3-dimensional
"clump" of RNA that will act as a site for protein assembly.
-Transfer RNA (tRNA): Transfer RNA is a cloverleaf-shaped strand of RNA that transfers/carries specific
amino acids to the site of protein assembly.
-Protein Polymerase: the enzyme that creates peptide bonds, attaching amino acids together to form a
protein
-Glycine or another amino acid: one of the building blocks of proteins, attached together by peptide
bonds during protein synthesis.
Stages of cell cycle - (answer)Differentiation begins:
-cell born
A+
What is the BASE PAIRING RULE for DNA? - (answer)A=T
C=G
What is the base pairing rule for RNA? - (answer)A=U
C=G
During the s-phase of interphase, the cell replicates its DNA using "SEMI-CONSERVATIVE REPLICATION".
Explain WHAT this means and WHY it is so important - (answer)WHAT: Way to copy DNA using master
strand as instructions on how to build the other side
-half of something is going to be conserved, half preserved
WHY: It's a very careful way to copy DNA
Explain exactly what happens during "semi-conservative DNA replication" - (answer)The cell will use
SEMI - CONSERVATIVE DNA REPLICATION to copy all
of its DNA prior to mitosis or meiosis. In this process, the original (master?) strand of DNA will be split in
half by DNA HELICASE and then DNA POLYMERASE will copy each half to produce two new and identical
DNA molecules from the original.
List 3 differences between DNA and RNA - (answer)DNA:
-double stranded
-nitrogenous bases: ATCG
-base pairing rule: A=T & C=G
-location: nucleus
RNA:
-single stranded
-nitrogenous bases: AUCG
,Bio 156 Exam 3 Questions & Answers (Updated 2026/2027) Already Graded
A+
-base pairing rule: A=U & C=G
-location: nucleus & cytoplasm
What is a chromosome? Draw a "duplicated CHROMOSOME" and LABEL all the parts
WHEN do chromosomes first appear in the cell cycle? - (answer)Chromosome: Condensed/compressed
superspooled DNA molecule
WHEN: during PROPHASE
(label parts: centromere & sister chromatids)
Describe 2 cellular events that happen during INTERPHASE
Describe 2 cellular events that happen during INTERPHASE - (answer)-Cell growth
-DNA replication
-Protein synthesis
(more specifically)...
-G1 phase = cell growth, organelles double
-S phase = synthesis of DNA, semi-conservative DNA replication
-G2 phase = protein synthesis, preparation for mitosis +++
-G0 phase = specialized cell "jobs" = secretion, muscle contraction,
Use the mRNA strand and the CODON KEY (On back) to answer the following questions;
a. describe the nucleotide sequence of the original DNA strand used to make the mRNA &
b. describe the primary structure of the protein in the gene on this DNA. - (answer)DNA TAC AAA TCT
CCA TTT GGG ACG ATT
mRNA AUG UUU AGA GGU AAA CCC UGC UAA
Protein Start●Phe● Arg●Gly● Lys●Pro●Cys● Stop
, Bio 156 Exam 3 Questions & Answers (Updated 2026/2027) Already Graded
A+
BRIEFLY describe the function/role of all these molecules in the protein synthesis "story".
adenine, thymine, cytosine, guanine ♦DNA polymerase ♦DNA unzipase/Helicase RNA polymerase
♦Messenger RNA (mRNA) ♦Ribosomal RNA (rRNA) ♦Transfer RNA (tRNA) ♦glycine or any another amino
acid ♦protein polymerase - (answer)-Adenine, thymine, cytosine, guanine: monomer nucleotides used
to form the DNA polymer.
-DNA polymerase: the enzyme that copies and repairs DNA.
-DNA unzipase/Helicase: the enzyme that separates the two sides of the DNA molecule by disrupting
the hydrogen bonds between complimentary nucleotides.
-RNA polymerase: the enzyme that copies and repairs RNA
-Messenger RNA (mRNA): the the actual copy of the DNA GENE, a nucleotide recipe for a single protein
-Ribosomal RNA (rRNA): is a strand of RNA which will form a RIBOSOME. A ribosome is a 3-dimensional
"clump" of RNA that will act as a site for protein assembly.
-Transfer RNA (tRNA): Transfer RNA is a cloverleaf-shaped strand of RNA that transfers/carries specific
amino acids to the site of protein assembly.
-Protein Polymerase: the enzyme that creates peptide bonds, attaching amino acids together to form a
protein
-Glycine or another amino acid: one of the building blocks of proteins, attached together by peptide
bonds during protein synthesis.
Stages of cell cycle - (answer)Differentiation begins:
-cell born
