CBSE
Multiple Choice QuestionsHow many different types of gametes are produced, if the genotype of a plant is AABB?
8
6
4
2
2
Which among these are correctly matched
(i) Down's syndrome - trisomy 21
(ii) Klinefelter's syndrome - 45, XO
(iii) Turner's syndrome - 47x XXY
(ii) and (iii) only
(i) only
(i) and (ii) only
(iii) only
(iii) only
What map unit (centimorgan) is adopted in the construction of genetic maps?
a unit of distance between two expressed genes representing 100%cross over.
a unit of distance between genes on chromosomes, representing 1% cross over.
a unit of distance between genes on chromosomes, representing 50% cross over.
a unit of distance between two expressed genes representing 10% cross over.
A gene locus has two alleles A, a. If the frequency of dominant allele A is 0.4, then what will be the frequency of homozygous dominant, heterozygous and homozygous recessive individuals in the population?
0.16 (AA); 0.24 (Aa); 0.36 (aa)
0.16 (AA); 0.48 (Aa); 0.36 (aa)
0.16 (AA); 0.36 (Aa); 0.48 (aa)
0.36 (AA); 0.48 (Aa); 0.16 (aa)
Select the incorrect statement.
Inmale grasshoppers 50% of sperms have no sex chromosomes.
In domesticated fowls, sex of progeny depends on the type of sperm rather than egg.
Human males have one of their sex-chromosome much shorter than the other.
Male fruit fly is heterogametic.
In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F1 generation pink flowers were obtained. When pink flowers were selfed, the F2 generation showed white, red and pink flowers. Choose the incorrect statement from the following :
Pink colour in F1 is due to incomplete dominance.
Ratio of F2 is
Law of segregation does not apply in this experiment
This experiment does not follow the Priniciple of Dominance
The frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes was explained by :
Gregor J. Mendel
Alfred Sturtevant
Sutton Boveri
T.H. Morgan
Variations caused by mutation, as proposed by Hugo de Vries are
random and directionless
small and directional
small and directionless
random and directional
What is the genetic disorder in which an individual has an overall masculine development gynaecomastia, and is sterile ?
Klinefelter's syndrome
Edward syndrome
Down's syndrome
Turner's syndrome
