How many meiosis will be required to produce 102 pollen-grains ?
25
25.6
26
26.5
Correct Answer :
C. 26
Related Questions
A colour-blind man marries the daughter of a colour-blind person. In their progeny
none of her daughters are colour-blind
all her sons are colour-blind
all her daughters are colour-blind
half of her sons are colour-blind
Transfer of a gene or genes through a virus is called
transformation
transduction
genetic engineering
sex-duction
A chemical mutagen is
X-rays
UV-rays
-rays
5-Bromo-Uracil
A child is bom with an extra chromosome in each of its cells. This is usually the result of
nondisjunction
crossing over
segregation
hybridization
Linkage is
directly related to crossing over
same as translocation
inversely related to crossing over
opposite to segregation
In humans, an example of sex-linked trait is
Curly hair
Sickle-cell anaemia
Colour-blindness
Down's syndrome
When is the sex of an offspring decided
At ovulation
During meiosis
During cleavage
At fertilization
If an individual does not breed true for its characters, it is called
homozygote
allelomorph
hybrid
ecotype
The first person to induce mutations was
Hugo de Vries
T.H. Morgan
Sturtevant
H.J. Muller
Reverse transcription was discovered by
Watson
Crick
Temin
Porter
Exhibition of superiority by a hybrid over both of its parents is called
heterosis
hybridization
hypostasis
dominance
Albinism in com plants is best described as
lethal
sex-linked
inbred
dominance
When two genes are situated very close to each other in a chromosome
the percentage of crossing over between themis high
hardly any cross-overs detected
no crossing-over can ever take place between them
only double cross overs can take place between them.
The segment of DNA which participates in crossing over is known as
recon
muton
criston
replicon
A codon is a sequence of 3 nucleolides on
t-RNA
m-RNA
s-RNA
hn-RNA
The best method to determine whether an individual is homozygous or heterozygous is
inbreeding
cross-breeding
back-crossing
self-fertilization
An offspring of two homozygous parents different from one another by alleles at only one gene locus is known as
monohybrid
dihybrid
trihybrid
backcross
Among the following which is a test cross?
TtxTt
TTxTT
TTxTt
Ttxtt
A person meets with an accident and great loss of blood has occurred. There is no time to analyse his blood group. It is safe to transfuse blood of
In a monohybrid cross the Fi ratio of a backcross is
1:1
3:1
1:2:1
9:3:3:3
A pure tall pea plant was reared in a soil poor in nutrition and reached the size of a pure dwarf pea plant If the plant is selfed, the genotype in the Fi generation is most likely to be
all tall
50% tall and 50% dwarf
all dwarf
data insufficient
Some people experience PTC paper on tongue as bitter, others as tasteless. This character is hereditary in nature. Suppose T stands for dominant gene and t for recessive gene, the genetic make up of a person who cannot taste is
TT
Tt
tt
None of these
The scientists who rediscovered the Mendel's laws are
Mast and Pantin
Watson and Crick
Corren, Tschermark and Hugo de Vries
Khorana and Nirenberg
Diakinesis is characterised by
crossing over
synapse
chiasmata
terminalization
The number of characters investigated by Mendel was
four
seven
six
one
DNA duplication occurs in
meiosis only
meiosis II and mitosis
mitosis only
meiosis I and mitosis
Base substitutions from base analogues I are called
transitions
transversions
intragenic complimentation
intergenic complimentation
A functional unit of a gene which specifies synthesis of one poly-peptide is known as
clone
recon
cistron
codon
Colour blindness is caused due to
deficiency of vitamic C
sex-linked abnormality
absence of rods in retina
absence of visual purple in retina
The crossing of a homozygous tall plant with a dwarf would yield plants in the ratio of
all heterozygous tall
two tall and two dwarf
one homozygous tall, two heterozygous tall and one homozygous dwarf
all homozygous dwarf.