2250 - Principles of Genetics - Dr. Carr
Sample exam questions (for Midterms I & II, & Final Exam)
are intended to show the STYLE
of questions that MAY
be asked on exams, NOT the specific questions
that will be asked.
For all exams, you will be given a sheet with the Universal Genetic Code: therefore it is not necessary to memorize the genetic code.
I. MOLECULAR BIOLOGY: For each question, indicate in the space provided the LETTER of the ONE response that best answers the question.
In double-stranded RNA
regions, the bonds that hold complementary nucleotides
together are described as
A. ionic B. covalent C. hydrophobic D. hydrogen E. hydrophilic
______ A ribonucleoside
includes a two-ring nitrogenous group with two H-bonds.
It is best described as:
A. dA B. dC C. dG D. dT E. dU
_______ If the sequence of a codon is 5'‑CGA‑3' , the sequence of the corresponding template strand is
5'-CGA-3' B. 5'-TCG-3' C. 5'‑UCG‑3'
For each of the following, indicate the type(s) of nucleic acid in which they are found [use ds, hn, m, r, and t for dsDNA, hnRNA, mRNA, rRNA, tRNA]
________ , ________ introns, anticodons
________ , ________ E sites, initiation sites
______ If the template strand of a
piece of DNA reads 3' - AAAAAATTT - 5', its
protein product will read:
A. H3N - F F K - COOH B. HOOC - F K K - NH3 C. H3N - K F F - COOH D. HOOC - K K F - NH3
The tertiary structure of protein is determined by
A. beta sheets B. hydrogen bonds C. disulfide bonds D. alpha helices E. subunit arrangement
______ The active site of an
enzyme is most likely
to be composed of amino acids with the following
A. Polar & Hydrophobic B. Polar & Hydrophilic C. Non-polar & Hydrophobic D. Non-polar & Hydrophilic
Semi-conservative DNA replication was demonstrated
A. Watson & Crick B. Meselson & Stahl C. Hershey & Chase D. Luria & Delbruck E. Penn & Teller
II. MOLECULAR GENETICS. Each of the following five statements contains a basic misconception about genetics. In not more than three grammatically complete sentences, identify and correct the error. Do NOT exceed the space provided. Do NOT draw diagrams.
Ex.: "Because it has higher energy, gamma radiation is always more mutagenic than alpha radiation."
Sample answer: Gamma radiation is more
energetic than alpha, but that energy is dispersed over a
much longer path length, so it has a lower linear energy
transfer (LET) than alpha radiation.
The higher LET of alpha radiation means that its lower energy will be dispersed over a very short path.
If the energy is released within the nucleus of a single cell near a chromosome, it will be highly mutagenic.
Ex.: "DNA probes
anneal to particular SNPs and are responsible for genetic
Ex.: "Met- mutants are caused by a defect of methionine that block its synthesis."
Ex.: "Most people do not have Cystic Fibrosis because
they do not have the gene for Cystic Fibrosis."
III. MENDELIAN GENETICS. For each question, indicate in the
space provided the LETTER of the ONE response that best answers
______ A woman is heterozygous for an X-linked recessive allele that causes night-blindness. If she marries a man with night-blindness, what proportions of her female & male offspring will carry the night-blindness allele?
A) all, none B) all, half C) half, half D) half, none E) none, half F) none, all
______ In Trufula trees, the locus for leaf color has three alleles: R (red), G (green), and B (brown). R is dominant to G, G is dominant to B. In the progeny of the cross BR x BG, what fraction will be brown ?
A) All B) 3/4 C) 1/2 D) 1/4 E) 0
______ Two individuals heterozygous for semi-dominant traits
at four loci are crossed: how many F2 genotypes are
A) 4 B) 9 C) 16 D) 27 E) 32 F) 64 G) 81
Sample answers: Your parents might both
heterozygotes with brown eyes, and you could be a blue-eyed
bb homozygote with blue eyes.
Eye color is likely a polygenic trait with multiple genes involved, so its inheritance is not that simple.
Ex.: Two people both
heterozygous for a recessive autosomal disease have a first
child born with the disease. Their physician tells them, "Don't
worry, your next three children will not have the disease."
IV. GENETIC STRUCTURES: Enter the correct LETTER for
each of the NUMBERED structure [see example].
The following DNA is part of a gene that
codes for a polypeptide of at least seven amino acids:
3' caattgattagtcagtcaattgat 5'
5' gttaactaatcagtcagttaacta 3'
i. Which strand includes an Open Reading Frame? Top (T) or Bottom (B) [2 pts]
ii. Which DNA strand is the sense strand? Top (T) or
Bottom (B) [2
iii. Give the mRNA sequence that would be transcribed from this gene; label the 5' & 3' ends. [3 pts]
iv. Give the seven amino acids that would be translated from the correct message; label the C & N ends. [5 pts]
translation problems can be generated from the app RandomORF
ANALYSIS: Given the pedigree shown, which of
the six modes of inheritance are possible?
Which is most likely? What observations would
TRI-HYBRID THREE-POINT TEST
CROSS: From the following recombination data,
draw a physical map to indicate the correct order and
distances between loci.
VIII. RESTRICTION MAPPING: From the following fragment size data, draw a restriction map. Label the sites, provide a scale.
Watson & Crick received
the Nobel Prize in what year?
(a) 1953 (b) 1962 (c) 1973
Transcription proceeds in which
of the following directions
(a) 3' 1' (b) 2' 4' (c) 3' 5' (d) 4' 6' (e) 5' 3'
Which carbon differs between
ribose and deoxyribose sugars? (a) 1' (b)
2' (c) 3' (d)
4' (e) 5'
Which of the following amino
acids is/are non-polar?
Draw the structure of Deoxyadenosine monophosphate.
Outline the process of
What are the clues for sex-linked inheritance?
How many introns are present in the chicken ovalbumin gene? (a) 4 (b) 5 (c) 6 (d)
7 (e) more than 7
Text material © 2016 by Steven M. Carr