An offspring of two homozygous parents different from one another by alleles at only one gene locus is known as
monohybrid
dihybrid
trihybrid
backcross
Correct Answer :
A. monohybrid
Related Questions
How many meiosis will be required to produce 102 pollen-grains ?
25
25.6
26
26.5
An offspring of two homozygous parents different from one another by alleles at only one gene locus is known as
monohybrid
dihybrid
trihybrid
backcross
A chemical mutagen is
X-rays
UV-rays
-rays
5-Bromo-Uracil
The scientists who rediscovered the Mendel's laws are
Mast and Pantin
Watson and Crick
Corren, Tschermark and Hugo de Vries
Khorana and Nirenberg
DNA duplication occurs in
meiosis only
meiosis II and mitosis
mitosis only
meiosis I and mitosis
In humans, an example of sex-linked trait is
Curly hair
Sickle-cell anaemia
Colour-blindness
Down's syndrome
Among the following which is a test cross?
TtxTt
TTxTT
TTxTt
Ttxtt
Down's syndrome is an example of
monosomy
trisomy
triploidy
polyploidy
The science dealing with study of inheritance and variation is
Genetics
Evolution
Morphology
Cytology
The chromosomal theroy of heredity implies that
chromosomes are composed of DNA and protein
genes are composed of chromosomes
organism cannot live withoutchromosomes
genes are located on the chromosomes and are transmitted to the next generation through them.
Which disease results from the genetic inability to synthesize a single enzyme ?
Diabetes
Phenylketonuria
Colour-blindness
Down's syndrome
When is the sex of an offspring decided
At ovulation
During meiosis
During cleavage
At fertilization
Base substitutions from base analogues I are called
transitions
transversions
intragenic complimentation
intergenic complimentation
The term 'meiosis' was coined bv
Herting and Van Beneden
Sutton and Boveri
Hofmeister and Waldeyer
Farmer and Moore
Chromosomes exhibit minimum coiling during
prophase
metaphase
interphase
telophase
In a monohybrid cross the Fi ratio of a backcross is
1:1
3:1
1:2:1
9:3:3:3
A giant chromosome having many chromo-nemata lying side by side all along their length is called
megachromosome
heterosome
polytene chromosome
super numerary chromosome
The segment of DNA which participates in crossing over is known as
recon
muton
criston
replicon
Which one of the following chemical characteristics is not common to all living beings ?
Similar triplet codes for amino acids
Energy is stored by high energy rich phosphate bonds
Types of protein present in the body.
Ribosomes act at sites of protein synthesis
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
The number of characters investigated by Mendel was
four
seven
six
one
The condition in which only one allele of a pair is present is known as
Homozygous
Heterozygous
Hemizygous
Incomplete dominance
The possibilities of hereditary and evolutionary changes are greatest in species that reproduce by
fission
budding
asexual means
sexual means
Transfer of a gene or genes through a virus is called
transformation
transduction
genetic engineering
sex-duction
The genetic constitution of an organism is known as
Genome
Genepool
Genotype
Phenotype
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
A child is bom with an extra chromosome in each of its cells. This is usually the result of
nondisjunction
crossing over
segregation
hybridization
Lethal genes are those which
cause the death of the organism in which they are present
cause the death of the homozygous infant being formed
cause the death of heterozygous infant being formed
all of the above
Diakinesis is characterised by
crossing over
synapse
chiasmata
terminalization
Albinism in com plants is best described as
lethal
sex-linked
inbred
dominance