In a plant species, flower colour yellow is dominant over white and fruit shape round is dominant over elongated. Crossing was performed between two pure lines - one having yellow-flower and round-fruit and another with white-flower and elongated-fruit. About 20 plants survived in F1 progeny. Plants of F1 were allowed to self-fertilise and about 960 plants survived in F2. If the traits follow Mendelian inheritance, the number of plants would have yellow-flower and round-fruit in F1 and F2 are respectively
20, 960
20, 540
10, 180
10, 60
A set of genes will be in a complete linkage when the progeny phenotypes for parental (P) and recombinant (R) types are
P = 0%, R =100%
P = 50%, R = 50%
P < 50%, R > 50%
P = 100%, R = 0%
Persons suffering from sickle-cell anaemia normally do not suffer from
cholera
malaria
high blood pressure
hepatitis
B.
malaria
Sickle-cell anaemia is a blood disease in which blood cells reveal an abnormal crescent (sickle) shape due to the point mutation at 6th position of -haemoglobin chain (glutamic acid valine). The resulted sickle-shape RBCs are resistant to attack by Plasmodium the vector of malarial disease.
Which one of the following information is essential to, determine the genetic map distance between two genes located on the same chromosome?
Length of the particular chromosome
Number of genes present in the particular chromosome
Number of nucleotides in the particular chromosome
Percentage of crossing over or recombinant frequency between the two genes
Which one of the following statements is relevant to sex linked characters?
They always follow criss-cross inheritance
They do not follow criss-cross inheritance
They are mostly present on Y-chromosome
They are only present on X-chromosome
A male rabbit of genotype 'AABBDDEE' is crossed with a female rabbit of genotype 'aabbddee' to produce F1 hybrid offspring. How many genetically different gametes can be produced by this F1 hybrid?
4
8
16
32
Match the items in column I with those in column II and choose the correct answer.
Column I | Column II |
A. Klinefelter syndrome | 1. Mutation in autosomal gene |
B. Thalassaemia | 2. Mutation in sex chromosome linked gene |
C. Down syndrome | 3. Trisomy of autosome |
D. Colour blindness | 4. Trisomy of sex chromosme |
A- 1; B- 2; C- 3; D- 4
A- 2; B- 3; C- 4; D- 1
A- 3; B- 4; C- 1; D- 2
A- 4; B- 1; C- 3; D- 2
Choose the correct statements regarding genetic disorders.
I. Turner's female is result of aneuploidy.
II. Tritanopia is a sex-linked recessive disorder.
III. Haemophilia-C follows criss-cross pattern of inheritance.
IV. Sickel cell anaemia is due to mutation of alleles in chromosome 11.
I, IV
II, III
I, III
II, III
The type of mutation in the nucleotide sequence given below is
Transition
Transversion
Deletion
Inversion
Marfan syndrome, a dominant single gene defect is characterised by lens dislocation, long limbs, spindly fingers, caved in chest and weakened aorta. This is an example of
Complete dominance
Epistasis
Pleiotropy
Codominance