Multiple Choice Questions9: 3: 3: 1 ratio is modified to 9 : 7 ratio due to
complementary gene
epistatic gene
hypostatic gene
supplementary gene
The map distance between the genes A and B is 3 units, between B and C is 10 units and between C and A is 7 units. The order of the genes in a linkage map constructed on the above data would perhaps be
A, B, C
A, C, B
B, C, A
B, A, C
One of the following is sex-influenced character
Appearance of beard
Baldness in male
Docile behaviour of female
Low BMR in female
A person with the sex chromosomes XXY suffers from :
Down's syndrome
Turner's syndrome
Gynandromorphism
Klinefelter's syndrome
D.
Klinefelter's syndrome
Klinefelter's syndrome is a chromosomal abnormality due to which an individual has two X-chromosomes and one Y-chromosome ie, XXY. Such persons are sterile male and may exhibit secondary female characters.
Down syndrome is also known as Trisomy- 21. It is a genetic disorder caused by the presence of extra copy of chromosome on 21st chromosome.
Turner's syndrome is a chromosomal condition that affects development in females. It consists of only 45 pairs of chromosomes ie, it is represented as X0. Females with this type of disease have short stature.
A gynandromorph can have bilateral asymmetry; one side female and one side male. Alternatively, the distribution of male and female tissue can be more haphazard. Bilateral gynandromorphy arises very early in development, typically when the organism has between 8 and 64 cells.
Which one of the following conditions in chromosome number is called monosomy?
2n + 1
2n + 2
2n - 1
2n - 2
Indicate, the inheritance of which of the following is controlled by multiple alleles?
Colourblindness
Sickle cell anaemia
Blood group
Phenylketoneuria
Which of the following conditions is related to haemophilia?
A responsible recessive gene present in the X-chromosome
A responsible dominant gene presentin the X-chromosome
A responsible dominant gene present in the Y-chromosome
A responsible dominant gene present in the autosomal chromosome
The absence of which clotting factor leads to haemophilia-A?
Factor VII
Factor VIII
Factor IX
Factor X
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