General Science 8th Class Chapter 4 Biotechnology Solved Exercise

General Science

8th Class

Chapter 4

Biotechnology

Questions

1. Encircle the correct option.

(i) The additional circular pieces of DNA present in a bacterial cell are called:

a. RNA        b. nucleotides        c. chromatids        d. plasmids

(ii) What may be the objective of genetic modifications of plants?

a. Production of disease resistant plants

b. Improvement in nutritional quality of plants

c. Production of herbicide resistant plants

d. All of these

(iii) Plasmid and attached foreign gene with it are collectively called:

a. recombinant cell        b. recombinant DNA

c. recombinant plasmid        d. recombinant chromosome

(iv) The organisms whose cells and plasmids are usually used in genetic engineering are:

a. bacteria        b. fungi        c. algae        d. viruses

(v) Sections of DNA serving as codes for developing characters in an organism are called:

a. genes        b. nucleotides        c. plasmids        d. proteins

(vi) Which of the following is not a biotechnology product?

a. Insulin        b. Quinine        c. Beta-endorphin        d. Interferon

(vii) How do genetic engineers get insulin for diabetic patients?

a. Isolate from human pancreas

b. Isolate from pancreas of other animals

c. Insulin gene inserted in human pancreas

d. Insulin gene inserted in bacteria

(viii) Why do genetic engineers use bacteria in genetic engineering?

a. The chromosome of bacteria is made of DNA and proteins

b. Their nucleus is very big and easy to handle

c. They have many chromosomes

d. Bacteria divide very fast and make colonies

(ix) A gene is inserted into a bacterium by:

a. tissue culture        b. fermentation        c. biodegradation        d. genetic engineering

2 Write short answers.

(i) What is biotechnology?

Ans.

Biotechnology:

Biotechnology is the use of living cells and organisms in the products and processes that can improve the quality of life.

(ii) Name at least two life saving products of biotechnology.

Ans.

Two important life saving biotechnology products include insulin and vaccines.

(iii) Write the application of biotechnology in

(a) agriculture        (b) health        (c) food production

Ans.

(a) agriculture

Biotechnology has played a revolutionary role in improving our agriculture and production of high yields of crops. Using biotechnology scientists insert weed resistance and pest resistance genes into the plants. Such genetically modified plants prepare proteins which are harmful for weeds and pest / insects. The major crops that have been modified are maize (corn), wheat, rice, canola, potato, soybean, cotton, etc.

(b) health

Biotechnology techniques are used for curing diseases and improving health. The diseases for which previously no adequate treatment was available can now be treated using biotechnology techniques. Identification of root causes of diseases, production of medicines for fighting against diseases and curing and correction of genetic defects, etc., are the major roles of this technology in developing better health.

(c) food production

Use of better quality genes in the animals is producing high yields of milk and meat. Production of better quality fruits and vegetables and increasing their shelf lives are also due to using biotechnology logical techniques.