Practicing Success

Target Exam

CUET

Subject

Biology

Chapter

Strategies for enhancement in Food production

Question:

Match List -I with List-II.

List -I(Animal breeding) List-II(Type)
(A) Crossing tall F2 progeny with recessive parent to determine its genotype (I) Cross-breeding
(B) Breeding within the same breed with no common ancestor (II) Inter-specific hybridization
(C) Breeding of superior male of one breed with the superior female of another breed (III) Test-crossing
(D) Breeding of animals of two different but related species   (IV) Out-crossing

  Choose the correct answer from the options given below:

Options:

(A)-(I), (B)-(II), (C)-(III), (D)-(IV)

(A)-(II), (B)-(I), (C)-(III), (D)-(IV)

(A)-(I), (B)-(II), (C)-(IV), (D)-(III)

(A)-(III), (B)-(IV), (C)-(I), (D)-(II)

Correct Answer:

(A)-(III), (B)-(IV), (C)-(I), (D)-(II)

Explanation:

Out-breeding : Out-breeding is the breeding of the unrelated animals, which may be between individuals of the same breed but having no common ancestors for 4-6 generations (out-crossing) or between different breeds (cross-breeding) or different species (inter-specific hybridisation).

Out-crossing: This is the practice of mating of animals within the same breed, but having no common ancestors on either side of their pedigree up to 4-6 generations. The offspring of such a mating is known as an out-cross. It is the best breeding method for animals that are below average in productivity in milk production, growth rate in beef cattle, etc. A single outcross often helps to overcome inbreeding depression.

Cross-breeding: In this method, superior males of one breed are mated with superior females of another breed. Cross-breeding allows the desirable qualities of two different breeds to be combined. The progeny hybrid animals may themselves be used for commercial production. Alternatively, they may be subjected to some form of inbreeding and selection to develop new stable breeds that may be superior to the existing breeds. Many new animal breeds have been developed by this approach. Hisardale is a new breed of sheep developed in Punjab by crossing Bikaneri ewes and Marino rams.

Interspecific hybridisation: In this method, male and female animals of two different related species are mated. In some cases, the progeny may combine desirable features of both the parents, and may be of considerable economic value, e.g., the mule.

When you cross a tall F2 progeny (a plant with a dominant tall trait) with a recessive parent (a plant with a homozygous recessive short trait), the purpose is typically to determine the genotype of the tall F2 plant. This type of cross is often referred to as a test cross .