LEC BIOC 1005 - Medical Genetics Questions With
Correct Answers ( Answers are at the bottom of the
paper) 2025/2026 a+
1 – Genetics Primer
1) Which of the following is a variant form of a gene, which has a different DNA
sequence and therefore produces a different product?
a) Gene
b) Allele
c) Locus
d) Genotype
e) Phenotype
2) Which of the following is a continuous DNA molecule with associated proteins that
carries genetic information in cells?
a) Genome
b) Chromosome
c) Mitosis
d) Meiosis
e) Locus
3) Which of the following means having only one copy of a gene, such as X-linked genes
in XY males?
a) Diploid
b) Haploid
c) Homozygous
d) Heterozygous
e) Hemizygous
4) Polymorphism describes an allele of a gene that is present in greater than what
percentage of a population, and has no easily discerned effect on phenotype of the
organism?
a) 99%
b) 75%
c) 50%
d) 25%
e) 1%
5) How many autosomes exist for humans?
a) 1
b) 22
c) 23
d) 44
e) 46
6) Sister chromatids attach to the centromere during which phase of mitosis?
a) Prophase
b) Metaphase
c) Anaphase
d) Telophase
e) None of the above
7) What chromosome is the β-globin chain of hemoglobin (Hb) on?
-1-
,a) 1
b) 11
c) 13
-2-
, d) 21
e) 23
8) Which of the following is true for carriers of sickle cell anemia?
a) Have sickle hemoglobin (HbS) but no anemia
b) Have normal hemoglobin (HbA) but no anemia
c) Have normal hemoglobin (HbA) and sickle hemoglobin (HbS) but no anemia
d) Have sickle hemoglobin (HbS) and have anemia
e) Have normal hemoglobin (HbA) and have anemia
f) Have normal hemoglobin (HbA), sickle hemoglobin (HbS) and have anemia
9) Most photographs of chromosomes are taken in what phase, which contains twice as
much DNA as do chromosomes in the majority of the cell cycle?
a) Prophase
b) Metaphase
c) Anaphase
d) Telophase
e) None of the above
Match the following descriptions with the chromosomal term:
10) Centromere is near one end; short arms (p) are very small a) Metacentric
11) Centromere is offset from center; arms are of different lengths b) Submetacentric
12) Centromere is near the center; arms are of nearly equal length c) Acrocentric
13) If one chromosome had two particular alleles at two different loci (A and B) and
another had different alleles at the same loci (a and b), which of the following are
possible with crossing over (which is more likely with increased gene distance)?
a) A and B or a and b
b) A and a or B and b
c) A and b or B and a
d) None of the above
14) Up to what percentage of all pregnancies result in the birth of a child with a
significant genetic or birth defect?
a) 9%
b) 7%
c) 5%
d) 3%
e) 1%
15) What is the recurrence risk for an autosomal dominant disorder?
a) 0%
b) 25%
c) 50%
d) 75%
e) 100%
2 –Introduction To DNA Technology
1.1) Which of the following advances in DNA technology has made it possible to
produce insulin and human growth factor?
a) Ability to cut, modify, reassemble, and analyze DNA
-3-
, b) Ability to select, characterize, mutate in a pre-determined manner, and even
synthesize individual genes
c) Ability to clone and express individual genes to produce the proteins they
encode in large amounts
d) Ability to determine and locate the gene mutations responsible for genetic
diseases
e) Ability to diagnosis sufferers and carriers of genetic diseases
f) Ability to plan future therapies that involve manipulation or replacement of
genes
1.2) Which of the following allows a segment of DNA to be amplified from down to one
cell into millions of copies in a few hours?
a) DNA purification and enzymes
b) Reverse transcription of RNA
c) Exploitation of base-pairing specificity in hybridization techniques
d) The development and manipulation of vectors and vectored host cells
e) The development of the polymerase chain reaction
2.1) Which of the following is most likely a restriction site sequence?
a) 5’ GAATTC, 3’ CTTAAG
b) 5’ GAATTC, 3’ CUUAAG
c) 5’ GATCATGCAT, 3’ CTAGTACGTA
d) 5’ GATCATGCAT, 3’ CUAGACGUA
e) 5’ CUAGACGUA, 3’ GATCATGCAT
2.2) Restriction endonucleases (restriction enzymes) are enzymes that cut
(hydrolyze) into smaller fragments.
a) Viral; DNA
b) Viral; RNA
c) Bacterial; DNA
d) Bacterial; RNA
2.3) Restrictions enzymes that create staggered cuts with a special affinity (if reunited)
leave ends, where the ends are stranded.
a) Blunt; Single
b) Blunt; Double
c) Sticky; Single
d) Sticky; Double
2.4) A linker is a short synthetic piece of that can attach to make ends become
.
a) RNA; Sticky; Blunt
b) RNA; Blunt; Sticky
c) DNA; Sticky; Blunt
d) DNA; Blunt; Sticky
2.5) Which of the following synthesizes a DNA strand that is complementary to an RNA
strand?
a) DNA ligase
b) DNA polymerase
c) Reverse transcriptase
d) Restriction endonuclease
-4-
Correct Answers ( Answers are at the bottom of the
paper) 2025/2026 a+
1 – Genetics Primer
1) Which of the following is a variant form of a gene, which has a different DNA
sequence and therefore produces a different product?
a) Gene
b) Allele
c) Locus
d) Genotype
e) Phenotype
2) Which of the following is a continuous DNA molecule with associated proteins that
carries genetic information in cells?
a) Genome
b) Chromosome
c) Mitosis
d) Meiosis
e) Locus
3) Which of the following means having only one copy of a gene, such as X-linked genes
in XY males?
a) Diploid
b) Haploid
c) Homozygous
d) Heterozygous
e) Hemizygous
4) Polymorphism describes an allele of a gene that is present in greater than what
percentage of a population, and has no easily discerned effect on phenotype of the
organism?
a) 99%
b) 75%
c) 50%
d) 25%
e) 1%
5) How many autosomes exist for humans?
a) 1
b) 22
c) 23
d) 44
e) 46
6) Sister chromatids attach to the centromere during which phase of mitosis?
a) Prophase
b) Metaphase
c) Anaphase
d) Telophase
e) None of the above
7) What chromosome is the β-globin chain of hemoglobin (Hb) on?
-1-
,a) 1
b) 11
c) 13
-2-
, d) 21
e) 23
8) Which of the following is true for carriers of sickle cell anemia?
a) Have sickle hemoglobin (HbS) but no anemia
b) Have normal hemoglobin (HbA) but no anemia
c) Have normal hemoglobin (HbA) and sickle hemoglobin (HbS) but no anemia
d) Have sickle hemoglobin (HbS) and have anemia
e) Have normal hemoglobin (HbA) and have anemia
f) Have normal hemoglobin (HbA), sickle hemoglobin (HbS) and have anemia
9) Most photographs of chromosomes are taken in what phase, which contains twice as
much DNA as do chromosomes in the majority of the cell cycle?
a) Prophase
b) Metaphase
c) Anaphase
d) Telophase
e) None of the above
Match the following descriptions with the chromosomal term:
10) Centromere is near one end; short arms (p) are very small a) Metacentric
11) Centromere is offset from center; arms are of different lengths b) Submetacentric
12) Centromere is near the center; arms are of nearly equal length c) Acrocentric
13) If one chromosome had two particular alleles at two different loci (A and B) and
another had different alleles at the same loci (a and b), which of the following are
possible with crossing over (which is more likely with increased gene distance)?
a) A and B or a and b
b) A and a or B and b
c) A and b or B and a
d) None of the above
14) Up to what percentage of all pregnancies result in the birth of a child with a
significant genetic or birth defect?
a) 9%
b) 7%
c) 5%
d) 3%
e) 1%
15) What is the recurrence risk for an autosomal dominant disorder?
a) 0%
b) 25%
c) 50%
d) 75%
e) 100%
2 –Introduction To DNA Technology
1.1) Which of the following advances in DNA technology has made it possible to
produce insulin and human growth factor?
a) Ability to cut, modify, reassemble, and analyze DNA
-3-
, b) Ability to select, characterize, mutate in a pre-determined manner, and even
synthesize individual genes
c) Ability to clone and express individual genes to produce the proteins they
encode in large amounts
d) Ability to determine and locate the gene mutations responsible for genetic
diseases
e) Ability to diagnosis sufferers and carriers of genetic diseases
f) Ability to plan future therapies that involve manipulation or replacement of
genes
1.2) Which of the following allows a segment of DNA to be amplified from down to one
cell into millions of copies in a few hours?
a) DNA purification and enzymes
b) Reverse transcription of RNA
c) Exploitation of base-pairing specificity in hybridization techniques
d) The development and manipulation of vectors and vectored host cells
e) The development of the polymerase chain reaction
2.1) Which of the following is most likely a restriction site sequence?
a) 5’ GAATTC, 3’ CTTAAG
b) 5’ GAATTC, 3’ CUUAAG
c) 5’ GATCATGCAT, 3’ CTAGTACGTA
d) 5’ GATCATGCAT, 3’ CUAGACGUA
e) 5’ CUAGACGUA, 3’ GATCATGCAT
2.2) Restriction endonucleases (restriction enzymes) are enzymes that cut
(hydrolyze) into smaller fragments.
a) Viral; DNA
b) Viral; RNA
c) Bacterial; DNA
d) Bacterial; RNA
2.3) Restrictions enzymes that create staggered cuts with a special affinity (if reunited)
leave ends, where the ends are stranded.
a) Blunt; Single
b) Blunt; Double
c) Sticky; Single
d) Sticky; Double
2.4) A linker is a short synthetic piece of that can attach to make ends become
.
a) RNA; Sticky; Blunt
b) RNA; Blunt; Sticky
c) DNA; Sticky; Blunt
d) DNA; Blunt; Sticky
2.5) Which of the following synthesizes a DNA strand that is complementary to an RNA
strand?
a) DNA ligase
b) DNA polymerase
c) Reverse transcriptase
d) Restriction endonuclease
-4-
