CBSE Class 12 Biology Question Paper 2019 Set 09

CBSE Class 12 Biology Question Paper 2019 Set I. Students can download the last year board exams question papers using the link below. Free download of examination question papers with solutions. Last 10 year question papers should be practised to get better marks in examinations.

SECTION A

1. Why are papaya plants said to be dioecious ?

2. Name the pollutant attributed to be the cause of ‘ozone-hole’ over the Antarctica region.

OR

List the greenhouse gases other than carbon dioxide.

3. Write the scientific name of the organism Alexander Fleming worked on and discovered the first antibiotic. Was the organism he worked on a fungus or a bacterium ?

OR

Suggest a method to overcome excessive inbreeding depression.

4. What is ‘Saltation’ according to de Vries ?

5. Differentiate between a DNA and a RNA nucleotide.

SECTION B

6. State the importance of emasculation and bagging in carrying out artificial hybridization.

7. Mention the causes of chromosomal disorders in humans. How do these disorders occur ?

8. What is ‘carrying capacity’ of a species in a habitat ? Why is logistic growth model considered more realistic ?

9. What is ‘Ori’ ? State its importance during cloning of a vector.

OR

Explain the importance of ‘selectable marker’, with the help of a suitable example.

10. Why has the Indian Government set up the organisation named GEAC ?Give any two reasons.

OR

Give a schematic representation of the transformation of a pro-insulin into insulin. 

Please click the link below to download pdf file of CBSE Class 12 Biology Question Paper 2019 Set I.