Download PDF
Free download in PDF Mendelian and Post Mendelian Genetics Short Questions and Answers for competitive exams. These short objective type questions with answers are very important for Board exams as well as competitive exams. These short solved questions or quizzes are provided by Gkseries.
41
In order to find out the different types of gametes produced by a pea plant having the genotype AaBb it should be crossed to a plant with the genotype
[A]
AABB
[B]
AaBb
[C]
aabb
[D]
aaBB
42
In a plant, red fruit (R) is dominant over yellow fruit (r) and tallness (7) is dominant over shortness (t). If a plant with RRTt genotype is crossed with a plant that is rrtt,
[A]
25% will be tall with red fruit
[B]
50% will be tall with red fruit
[C]
75% will be tall with red fruit
[D]
all the offspring will be tall with red fruit
Answer: 50% will be tall with red fruit
43
A nutritionally wild type organism, which does not required any additional growth supplement is known as
[A]
phenotype
[B]
holotype
[C]
autotroph
[D]
prototroph
44
A male human is heterozygous for autosomal genes A and B and is also hemizygous for hemophilic gene h. What proportion of his sperms will be abh?
[A]
1/8
[B]
1/32
[C]
1/16
[D]
1/4
45
Lack of independent assortment of two genes A and B in fruit fly Drosophila is due to
[A]
repulsion
[B]
recombination
[C]
linkage
[D]
crossing over
46
One of the parents of a cross has a mutation in its mitochondria. In that cross, that parent is taken as a male. During segregation of F2 progenies that mutation is found in
[A]
one-third of the progenies
[B]
none of the progenies
[C]
all the progenies
[D]
fifty percent of the progenies
Answer: none of the progenies
47
Which one of the following traits of garden pea studied by Mendel was a recessive feature?
[A]
axial flower position
[B]
green seed colour
[C]
green pod colour
[D]
round seed shape
Answer: green seed colour
48
The genes controlling the seven pea characters studied by Mendel are now known to be located on how many different chromosomes?
[A]
seven
[B]
six
[C]
five
[D]
four
49
Two crosses between the same pair of genotypes or phenotypes in which the sources of the gametes are reversed in one cross, is known as
[A]
test cross
[B]
reciprocal cross
[C]
dihybrid cross
[D]
reverse cross
50
Which of the following is an example of pleiotropy ?
[A]
haemophilia
[B]
thalassemia
[C]
sickle cell anaemia
[D]
colour blindness
Answer: sickle cell anaemia
51
There are three genes a, b, c. Percentage of crossing over between a and b is 20%, b and c is 28% and a and c is 8%. What is the sequence of genes on chromosome?
[A]
b, a, c
[B]
a, b, c
[C]
a, c, b
[D]
none of these
52
On selfing a plant of F1 generation with genotype “AABbCC”, the genotypic ratio in F2-generation will be
[A]
3 : 1
[B]
1 : 1
[C]
9:3:3:1
[D]
27 : 9 : 9 : 9 : 3 : 3 : 3 : 1.
53
A gene is said to be dominant if
[A]
it expresses its effect only in homozygous state
[B]
it expresses its effect only in heterozygous condition
[C]
it expresses its effect both in homozygous and heterozygous condition.
[D]
it never expresses its effect in any condition
Answer: it expresses its effect both in homozygous and heterozygous condition.
54
Two nonallelic a gene produces the new phenotype when present together but fail to do so independently then it is called
[A]
epistasis
[B]
polygene
[C]
non complementary gene
[D]
complementary gene
55
A and B genes are linked. What shall be genotype of progeny in a cross between AB/ab and ab/ab
[A]
AAbb and aabb
[B]
AaBb and aabb
[C]
AABB and aabb
[D]
none of the above
56
When dominant and recessive alleles express itself together it is called
[A]
co-dominance
[B]
dominance
[C]
amphidominance
[D]
pseudo dominance
57
Ratio of complementary genes is
[A]
9:3:4
[B]
12 : 3 : 1
[C]
9 : 3 : 3 : 4
[D]
9 : 7
58
Independent assortment of genes does not takes place when
[A]
genes are located on homologous chromosomes
[B]
genes are linked and located on same chromosome
[C]
genes are located on non-homogenous chromosome
[D]
all the above
Answer: genes are linked and located on same chromosome
59
Due to the cross between TTRrxttrr the resultant progenies show what percent of tall, red flowered plants
[A]
50%
[B]
75%
[C]
25%
[D]
100%
60
Which one of the following is an example of polygenic inheritance?
[A]
skin colour in humans
[B]
flower colour in Mirabilis jalapa
[C]
production of male honey bee
[D]
pod shape in garden pea
Answer: skin colour in humans
Please share this page