Genetics Exam test queries and
answers graded A+
The expected phenotypic ratio in a dihybrid cross of two independently assorting genes showing
complete dominance is...
a) 15:1
b) 9:7
c) 3:1
d) 1:2:1
e) 9:3:3:1 - ANS✅✅e) 9:3:3:1
10 primary spermatocytes will give rise to ___ sperm cells, while 10 primary oocytes will give rise to
___ ova.
a) 400; 400
b) 40; 10
c) 10; 40
d) 400; 100
e) 100; 400 - ANS✅✅b) 40; 10
When are sister chromatids separated?
a) anaphase of mitosis
b) anaphase I of meiosis
c) anaphase II of meiosis
d) A & B
e) A & C - ANS✅✅e) A & C
In what phase of meiosis are human oocytes arrested?
a) pachynema
b) diplonema
c) leptonema
d) diakinesis
, e) zygonema - ANS✅✅b. diplonema
in mammals, such as humans, sex is determined by:
a. the presence of either haploid set or a diploid set of chromosomes
b. temperature during development
c. the number of X chromosomes present
d. the ratio of Y chromosomes to autosomes present
e. the SRY gene on the Y chromosome - ANS✅✅e. the SRY gene on the Y chromosome
Which of the following organisms s a nematode worm species, individuals of which are only found to
be either male or hermaphrodite?
a. Drosophila melanogaster
b. C. elegans
c. Saccharomyces cereviseae
d. Arabidopsis thaliana
e. Mus musculus - ANS✅✅b. C. elegans
Review the pedigree.
What mode or modes of inheritance are possible for the trait represented by this pedigree?
a. either autosomal dominant or autosomal recessive
b. autosomal dominant only
c. x-linked recessive
d. autosomal recessive only - ANS✅✅
Which of the following statements is FALSE regarding cell division?
a. alignment of homologous chromosomes during meiosis I is random and contributes to the genetic
diversity of gametes
b. cells spend most of their time in interphase
c. the gametes formed by a 2n individual can be expected to be 2n
d. mitosis results in two genetically identical daughter cells from one parent - ANS✅✅c. the
gametes formed by a 2n individual can be expected to be 2n
answers graded A+
The expected phenotypic ratio in a dihybrid cross of two independently assorting genes showing
complete dominance is...
a) 15:1
b) 9:7
c) 3:1
d) 1:2:1
e) 9:3:3:1 - ANS✅✅e) 9:3:3:1
10 primary spermatocytes will give rise to ___ sperm cells, while 10 primary oocytes will give rise to
___ ova.
a) 400; 400
b) 40; 10
c) 10; 40
d) 400; 100
e) 100; 400 - ANS✅✅b) 40; 10
When are sister chromatids separated?
a) anaphase of mitosis
b) anaphase I of meiosis
c) anaphase II of meiosis
d) A & B
e) A & C - ANS✅✅e) A & C
In what phase of meiosis are human oocytes arrested?
a) pachynema
b) diplonema
c) leptonema
d) diakinesis
, e) zygonema - ANS✅✅b. diplonema
in mammals, such as humans, sex is determined by:
a. the presence of either haploid set or a diploid set of chromosomes
b. temperature during development
c. the number of X chromosomes present
d. the ratio of Y chromosomes to autosomes present
e. the SRY gene on the Y chromosome - ANS✅✅e. the SRY gene on the Y chromosome
Which of the following organisms s a nematode worm species, individuals of which are only found to
be either male or hermaphrodite?
a. Drosophila melanogaster
b. C. elegans
c. Saccharomyces cereviseae
d. Arabidopsis thaliana
e. Mus musculus - ANS✅✅b. C. elegans
Review the pedigree.
What mode or modes of inheritance are possible for the trait represented by this pedigree?
a. either autosomal dominant or autosomal recessive
b. autosomal dominant only
c. x-linked recessive
d. autosomal recessive only - ANS✅✅
Which of the following statements is FALSE regarding cell division?
a. alignment of homologous chromosomes during meiosis I is random and contributes to the genetic
diversity of gametes
b. cells spend most of their time in interphase
c. the gametes formed by a 2n individual can be expected to be 2n
d. mitosis results in two genetically identical daughter cells from one parent - ANS✅✅c. the
gametes formed by a 2n individual can be expected to be 2n
