12th TEST MODEL 2019 (CBSE)

Time- 3hrs FM- 70

RAHMAN BIOLOGY CLASSES

CBSE BOARD EXAM

A. Question carrying 1 Marks:-

1.Write an alternate source of protein for animal and human nutrition.

2.How does camouflage help an insect?

3.State a difference between a gene and an allele.

4.'Man can be primary as well as secondary consumer'. Justify this statement.

5.Mention the role of Cyano bacteria as biofertiliser.

B. Question carrying 2 Marks:-

6.(a)How does a vaccine affect immunity?

(b)How can we get immunization against Polio?

7.Mention the contribution of SL Miller's experiment to origin of Life.

8.(a) Expand GIFT and ICSI

(b)Why is ZIFT a boon to childless couples?

9.What is amniocentesis? How is it misused?

10.Write the function of each one of the following:-

(a)Fimbriae (b)Oxytocin (c)Seminal vesicle

C. Question carrying 3 Marks:-

11.(a)List any four characteristic of an ideal contraceptive

(b)Name two intrauterine contraceptive devices that affects the motality of sperm.

12.What is the functional differences between B-cells and T-cells.

13.Name the causative organisms for the following diseases.

(a)Elephantiasis (b)Ringworm(c)Amoebiasis

14.Name and describe any three cause of biodiversity losses?

15.How are following used in biotechnology

(a)Plasmid D.N.A (b)Recognition sequences (c)Gel electrophoresis.

16.Determination of Biological oxygen Demond (BOD) can help in suggesting the quality of water body? Explain.

17.Explain the mechanism of 'Sex determination' in Human. How does it differ from that of Insects.

18.Name any one fowls (domestic birds) other than chicken reared in poultry farm.

19.Enlist important components of poultry farm management.

20.A antibody molecule is represented as H₂L₂. Explain.

21.Differentiate between benign and malignant tumors.

22.Describe endosperm development in angiosperm.

D. Question carrying 4 Marks:-

23.Community service department of your school plans a visit to a slum near the school with an objective to educate the slum dwellers with respect to health and hygine.

(i) Why is there a need to organize such visits?

(ii) Write the steps you will highlight as member of this department in your interaction with them to enable them to lead a healthy life.

(iii) What value is shown by your school department?

E. Question carrying 5 Marks:-

24. (a)Explain the process of spermatogenesis in humans.

‘OR’

(b)Draw a human sperm and label acrosome and middle piece. Mention their functions.

25. (a)Explain Mendel's law of independent assortment by taking a suitable example.

‘OR’

(b)How did Morgan show the deviation in inheritance pattern in Drosophila with

respect to this law?

26. (a) Given below is the schematic representation of lac operon of E. coli. Explain the functioning of this operon when lactose is provided in the growth medium of the bacteria.

‘OR’

(b) With the help of diagram show the different steps in the formation of recombinant DNA by action of restriction endonuclease enzyme EcoRI.

By- Zoya Rahman (9661394167)

12th TEST MODEL 2019 (CBSE)