University Test Questions With 100%
Accurate Answers 2025-2026 Edition.
Define mutation - Answer a random change in an allele
Mutations are caused by selective pressure in the environment. True or False - Answer False
The same mutation could be advantageous in some environments but deleterious in others.
True or False - Answer True
The appearance of dark-colored volcanic rock caused the mutation from black fur to appear in
the rock pocket mouse population? True or False - Answer False
Both DNA and RNA contain... - Answer phosphate groups
The number of consecutive mRNA bases needed to specify an amino acid is - Answer 3
If the sequence of bases in a section of DNA is 5'—TAGGCTAA -3', what is the corresponding
sequence of bases in mRNA? - Answer 3'—AUCCGAUU-5'
What is a ribozyme - Answer An RNA with enzymatic activity
What is an anticodon? - Answer 3 consecutive nucleotides in tRNA
The process of copying genetic information from DNA to RNA is called - Answer Transcription
A transcription start signal is called - Answer A promoter
A type of RNA that binds to a specific amino acid during translation is - Answer Transfer RNA
Which of the following statements describes a eukaryotic chromosome? - Answer A single
,The leading and the lagging strands differ in that - Answer The leading strand is synthesized in
the same direction as the movement of the replication fork, and the lagging strand is
synthesized in the opposite direction
In E.coli, there is a mutation in a gene called dnaB that alters the helicase that normally acts at
the origin. Which if the following would you expect as a result of this mutation? - Answer No
replication fork will be formed
After DNA replication is completed - Answer Each new DNA double helix consists of one old
DNA strand and one new DNA strand
Which of the following represents the order of increasingly higher levels of organization of
chromatin? - Answer Nucleosome, 30 nm chromatin fiber, looped domain
If a cell were unable to produce histone proteins, which of the follow would be a likely effect? -
Answer The cell's DNA couldn't be packed into its nucleous
When chromosomes replicate... - Answer The two DNA strands separate and each is used as a
template for synthesis of a new strand
Sequence of subunits in the DNA "backbone" is - Answer -phosphate—sugar—phosphate—
sugar—phosphate—sugar--
One organism has 18% cytosine in its genome, how much adenine does it have? - Answer 32%
Two strands of duplex DNA are complementary in sequence and arranged in antiparallel
fashion. What is the base sequence of the complementary strand to the following: 5'—
ATGCTCGACTTACAT—3' - Answer 5'—ATGTAAGTCGAGCAT—3'
Which of the following can be found in both DNA and RNA nucleotides? - Answer Phosphate,
ribose, pyrimidine, purine, adenine, guanine, cytosine
In a DNA double helix structure, what is the function of hydrogen bonds? - Answer Holding the
complementary base pairs together
, What is DNA packaging? - Answer Pairing DNA with other proteins and putting it together to
form chromatin
When Mendel crossed yellow-seeded and green-seeded plants, al the offspring were yellow
seeded. When he took these F1 yellow-seeded plants and crossed them to green-seeded plants,
what genotypic ratio was expected? - Answer 1:2:1
A woman is red-green colorblind, and she mates with a man who has normal color vision.
Knowing that red-green color blindness is controlled by a gene on the X chromosome, what can
you predict for their children with regard to inheritance of color vision? - Answer All of the
boys and none of the girls will be color blind
A woman with normal color vision, but whose father is red-green colorblind mates with a man
who is red-green colorblind. Knowing that red-green colorblindness is controlled by a gene on
the X chromosome, what can you predict for their children with regard to inheritance of color
vision? - Answer Half of the boys and half of the girls will be colorblind
What is true of genetic linkage? - Answer The closer the two genes are on a chromosome, the
lower the probability that a crossover will occur between them, linked genes are found on the
same chromosome, the frequency of recombination of two linked genes that are far apart from
each other is greater than those closer ones, crossing over can break the linkage
What are the sources of variety in sexually reproducing species? - Answer Crossing over,
random fertilization, and independent assortment
The region of the chromosome occupied by a gene is called a - Answer Locus
A recessive gene is one - Answer Whose effect is masked by a dominant allele
If, in a heterozygous individual, only one allele is expressed in the phenotype, that allele is -
Answer Dominant
When the two gametes that fuse to form a zygote contain different alleles of a given gene, the
offspring is - Answer Heterozygous