11.

A mechanism that can cause a gene to move from one linkage group to another is

• Crossing over

• Inversion

• Translocation

• Duplication

In a certain genetic cross, 1/ 16 proportion of progeny shows mutant phenotype. It means

• Two independent assorting genes are involved for trait

• Two independently assorting duplicate genes are involved

• Two linked genes are involved for trait

• Two independent segregating alleles areresponsible for trait

Sponatneity of mutation means

• Mutation in absence of exogenous mutagen     

• Mutation directly proportion to presence of mutagen   

• Mutation at in appropriate time    

• Mutation at in appropriate time

A mother of blood group O has a group A child. The father could be of the blood type

• A or B or O

• A only

• A or B

• AB only

Intracellular pathogens like Mycobacteria, Salmonella, Leismania and Listeria survive in macrophages by modulating host cellular machinery. In order to study the fate of these intracellular pathogens in macrophages, cells were labeled with  lysotracker Red arid infected with GFP labeled organisms. After 2 hours at 37^oC, cells er fixed, stained with anti‐transferrin receptor antibody and probed with secondary antibody conjugated blue dyes. Cells were viewed under confocal microscope Observation: GFP labeled mycobacteria, Salmonella and Listeria were localized in the same compartment labeled with blue dyes; whereas GFP Leishmania co‐localize with red labeled compartment.
Which of the following statement is true based on these observations?

• Mycobacteria, Salmonella and Listeria reside in the lysosomes

• Leishmania reside in lysosome like compartment

• Leishmania reside in compartment which bears characteristics of early endocytic compartment

• Mycobacteria, Salmonella and Listeria lyse the phagosomal membrane and reside in cytosol

Bacteria often acquire genes by the process of lateral or horizontal transfer. Such foreign gens, if acquired in recent past, may be identified by their typical GC content, as compared to native genes. Suppose the genomic GC content of a bacterium is 40%. Gene A of this organism contains 1000 bases with 225 G and 215 C. Another gene B of length 800 bases contain 160 G and 140 C. Which one of the following would be the most acceptable hypothesis (giving that Χ² = 3.841 at 0.05 significance level)?

• A native, B foreign

• A foreign, B native

• A foreign, B foreign

• A native, b native

In Neurospora a cross between the genotypes ‘A’ and ‘a’ results in an ascus with ascospores of genotypes as shown below:

Statements A to D are events that could have occurred during meiosis

A. Crossing over between the centromeres and the gene
B. Segregation of alleles ‘A’ and ‘a’ in meiosis I
C. Segregation of alleles ‘A’ and ‘a’ in meiosis II
D. Assortment of alleles ‘A’ and ‘a’

Which of the above events could correctly explain the observation shown in the figure?

• A followed by C

• C alone

• A followed by B

• D alone

When F1 female Drosophila of the genotype a+ab+bc+c is crossed, the following progenies were obtained:

Progeny classes	No.of progenies
a+b+c+	22
a+b+c	28
a b c+	26
a+b c+	24
a+b c	230
a b+ c+	220
a b+ c	225
total	1000

The progeny has been shown as classes derived from the female gamete.Statements A to F as given below are conclusions derived from the above result

A. Genes a and b are lined in cis
B. Genes a and b are linked in trans
C. Genes a and b are linked in cis while b and c are linked in trans
D. The genotype of the parents are a+a+b+b+ and aabb
E. The genopyte of the parents are a+a+bb and aab+b+
F. Genes a and b are 10 cM apart
Which of the above statements are correct?

• C alone

• A, E and F

• B, E and F

• A, D and F

The following is a hypothetical pathway for the development of wild type (red) eye colour in an insect:

$$\begin{gathered} \left.\begin{array}{r}\underset{(\mathrm{colorless} \mathrm{percursor})}{\mathrm{W}} \stackrel{\mathrm{Enzyme} \mathrm{A}}{\to }\underset{(\mathrm{orange} \mathrm{color})}{\mathrm{X}} \\ \underset{(\mathrm{colorless} \mathrm{percursor})}{\mathrm{Y}} \stackrel{\mathrm{Enzyme} \mathrm{A}}{\to } \underset{(\mathrm{brown} \mathrm{pigment})}{\mathrm{Z}}\\ \end{array}\right\} \mathrm{Red} \mathrm{eye} \mathrm{color} (\mathrm{wild} \mathrm{type} \end{gathered}$$

Enzyme A and B are encoded by the genes a⁺ and b⁺, respectively.

The following statements are made regarding inheritance of the genes involved in the develpments of eye color.

A. When two heterozygous individuals of the genotype a⁺ab⁺b are mated, progenies with red, orange, brown and white eye colour will be observed irrespective of whether the genes are independently assorting or showing incomplete linkage.

B. When two heterozygous individuals of the genotype a⁺ab⁺b are mated, progenies with red, orange, brown, and white eye colour will be observed in a ratio of 9:3:3:1, when the genes are independently assorting.

C. When an heterozygous individual of the genotype a⁺b/ab⁺ is test crossed, progenies with red and white eye colour will be more in number

D. When an heterozygous individual of the genotype a⁺b/ab⁺ is test crossed, progenies with orange and brown eye colour will be more in number.

Which of the above statements is true?

• A and C

• B and C

• A, B and C

• A, B and D

Mendel crossed tall pea plants with dwarf ones. The F1 plants were all tall. When these F1 plants were selfed to produce F2 generation, he got a 3:1 tall to dwarf ratio in the offspring. What is the probability that out of three plants (of F2 generation) picked up at random two would be dwarf and one would be tall?

• 3/4

• 3/8

• 9/64

• 9/32