Case Study Questions for Class 12 Biology Chapter 12 Biotechnology and Its Applications

Case Study Questions for Class 12 Biology Chapter 12 Biotechnology and Its Applications

Question 1:

Transgenic cows have extra gene or genes inserted into their DNA. Firstly the genes for the desired product is identified and sequenced. Then a gene construct containing this desired gene is introduced into female cow cells. Transgenic bovine cells are selected and fused with bovine oocytes that have had all of their chromosomes removed. Once fused with the oocyte, the transgenic cells chromosomes are reprogrammed to direct development which can be implanted into a recipient cow. The resulting transgenic cow only express the transgene in her milk. This is because expression of the transgene is controlled by a promoter specific to lactating mammary cells.

(i) The gene construct with desired gene is introduced into female cow cells by
(a) transformation
(b) transduction
(c) transfection
(d) transplantation.

(ii) Production of transgenic cow fulfill the objective of
(a) increased milk production
(b) increased meat production
(c) molecular farming
(d) all of these.

(iii) The name of first transgenic cow is
(a) Tracy
(b) Dolly
(c) Rosie
(d) ANDI.

(iv) Transgenic cow is produced through the implantation of ______ containing transgene into recipient cow.
(a) ova
(b) embryo
(c) mammary cell
(d) both (a) and (b)

(v) Read the given statements and select the correct option.
Statement I : Transgenes only express in the mammary glands of transgenic cow.
Statement II : Transgenes are present in chromosomes of every cell in transgenic cow.
(a) Both statements I and II are true.
(b) Both statements I and II are false.
(c) Statement I is true but statement II is false.
(d) Statement I is false but statement II is true.

Answer

Answer: (i) (c)
(ii) (d) : The two chief objectives of transgenic cow production are as follows : (i) increased milk and meat production and (ii) molecular farming.
(iii) (c)
(iv) (b) : Transgenic bovine cells are selected and fused with bovine oocytes that have had all its chromosomes removed. Once fused with oocyte, the transgenic cells chromosomes are reprogrammed to direct development into an embryo which is implanted into recipient cow.
(v) (a)