BIO 243 Midterm Exam Questions with Correct Answers Latest Update 2025/2026
genetics - Answers the study of genes
gene - Answers functional unit of heredity and variation
molecular genetics - Answers the study and function of genes at the molecular level
allele - Answers variant forms of a gene (eye colour)
genotype - Answers genes inherited by an organsm
phenotype - Answers visible traits ( behavior, eye colour)
genome - Answers entire DNA sequence of an organsim
gene expression - Answers turning on genes to produce RNA and proteins
protein expression - Answers the type and abundance of proteins in the cell
enzymes - Answers catalyzes reactions of all biomolecules
structural proteins - Answers maintenance of cell shape
signalling proteins - Answers hormones and receptors
Griffith experiment - Answers found a substance that could genetically transform bacteria, used
virulent bacteria on mice
Avery, MacLeod and McCarthy experiment - Answers identified DNA as the molecule that
transforms rough bacteria into the infective form
Hershey and Chase experiment - Answers found the final evidence that DNA is the heredity
molecule
lytic cycle - Answers massive replication of viruses in one host cell
lysogenic cycle - Answers replication of viral genome and passed on during replication
purines - Answers two rings of Nitrogen, Guanine, Adenine
pyrimidines - Answers one ring, Cytosine, Thymine, Uracil
nucleotides - Answers sugar molecule, base, phosphates attached to 5C
deoxynucleotides - Answers the building blocks of DNA
Chargaff's rule - Answers %A=&T, %C=%G
Rosalind Franklin - Answers created an X-ray photo of DNA showing an X pattern
, Watson and Crick - Answers used the X-ray of DNA to determine the double helix shape of DNA
with anti-parallel strands
A-T has how many hydrogen bonds? G-C has how many? - Answers 2, 3
prokaryotic chromosomes - Answers one circular chromosome, smaller independent
chromosomes in the cytoplasm called plasmids
eukaryotic chromosomes - Answers linear and enclosed in nucleus
chromatin - Answers a given region of DNA with its associated proteins on a chomosome
origins of replication - Answers DNA sequences that initiate DNA replication
centromere - Answers center dot that connects the two sister chromatids
telomere - Answers DNA sequences at the end that prevent degradation of coding DNA
dipliod - Answers (2n) two copies of each chromosome, homologous pairs
hapliod - Answers (n) one pair of chromosmes, found in sperm/eggs
histones - Answers positively charged proteins that DNA winds around
semi-conservative replication - Answers each daughter strand stays paired with its
complimentary parental strand
conservative replication - Answers after replication both daughter cells pair up
dispersion replication - Answers daughter strands have a mixture of parental and daughter DNA
nucleotides are added in what direction? - Answers 5' to 3', new bases can only be added at the
3' OH end
Replisome - Answers molecular machine of enzymes that replicate DNA
Helicase - Answers unwinds double helix
Primase - Answers synthesizes RNA primers
Gyrase - Answers removes supercoils
DNA pol 3 - Answers synthesizes new DNA by adding new nucleotide bases
DNA pol 1 - Answers removes RNA primer and fills gaps with DNA
sliding clamp - Answers attaches DNA pol 3 to DNA
Ligase - Answers joins ends of DNA together with phosphodiester bonds
genetics - Answers the study of genes
gene - Answers functional unit of heredity and variation
molecular genetics - Answers the study and function of genes at the molecular level
allele - Answers variant forms of a gene (eye colour)
genotype - Answers genes inherited by an organsm
phenotype - Answers visible traits ( behavior, eye colour)
genome - Answers entire DNA sequence of an organsim
gene expression - Answers turning on genes to produce RNA and proteins
protein expression - Answers the type and abundance of proteins in the cell
enzymes - Answers catalyzes reactions of all biomolecules
structural proteins - Answers maintenance of cell shape
signalling proteins - Answers hormones and receptors
Griffith experiment - Answers found a substance that could genetically transform bacteria, used
virulent bacteria on mice
Avery, MacLeod and McCarthy experiment - Answers identified DNA as the molecule that
transforms rough bacteria into the infective form
Hershey and Chase experiment - Answers found the final evidence that DNA is the heredity
molecule
lytic cycle - Answers massive replication of viruses in one host cell
lysogenic cycle - Answers replication of viral genome and passed on during replication
purines - Answers two rings of Nitrogen, Guanine, Adenine
pyrimidines - Answers one ring, Cytosine, Thymine, Uracil
nucleotides - Answers sugar molecule, base, phosphates attached to 5C
deoxynucleotides - Answers the building blocks of DNA
Chargaff's rule - Answers %A=&T, %C=%G
Rosalind Franklin - Answers created an X-ray photo of DNA showing an X pattern
, Watson and Crick - Answers used the X-ray of DNA to determine the double helix shape of DNA
with anti-parallel strands
A-T has how many hydrogen bonds? G-C has how many? - Answers 2, 3
prokaryotic chromosomes - Answers one circular chromosome, smaller independent
chromosomes in the cytoplasm called plasmids
eukaryotic chromosomes - Answers linear and enclosed in nucleus
chromatin - Answers a given region of DNA with its associated proteins on a chomosome
origins of replication - Answers DNA sequences that initiate DNA replication
centromere - Answers center dot that connects the two sister chromatids
telomere - Answers DNA sequences at the end that prevent degradation of coding DNA
dipliod - Answers (2n) two copies of each chromosome, homologous pairs
hapliod - Answers (n) one pair of chromosmes, found in sperm/eggs
histones - Answers positively charged proteins that DNA winds around
semi-conservative replication - Answers each daughter strand stays paired with its
complimentary parental strand
conservative replication - Answers after replication both daughter cells pair up
dispersion replication - Answers daughter strands have a mixture of parental and daughter DNA
nucleotides are added in what direction? - Answers 5' to 3', new bases can only be added at the
3' OH end
Replisome - Answers molecular machine of enzymes that replicate DNA
Helicase - Answers unwinds double helix
Primase - Answers synthesizes RNA primers
Gyrase - Answers removes supercoils
DNA pol 3 - Answers synthesizes new DNA by adding new nucleotide bases
DNA pol 1 - Answers removes RNA primer and fills gaps with DNA
sliding clamp - Answers attaches DNA pol 3 to DNA
Ligase - Answers joins ends of DNA together with phosphodiester bonds
