Total number of printed pages : 3 2020/XI/BIO
2020
BIOLOGY
Total marks : 70 Time : 3 hours
General instructions:
i) Approximately 15 minutes is allotted to read the question paper and revise the
answers.
ii) All questions are compulsory. Marks are indicated against each question.
iii) The question paper consists of two parts – Part A and Part B.
Each part contain 14 questions.
iv) Internal choice has been provided in some questions.
v) Write the answers of Part A and Part B in separate answer books.
Marks shall not be awarded if the answers of both the Parts are written in one
book nor marks awarded if answers of Part A are written in the answer book of
Part B and vice-versa.
N.B: Check that all pages of the question paper is complete as indicated on the top left side.
PART - A
1. Taxonomical aid used for identification of plants and animals based on
similarities and dissimilarities is called 1
(a) Taxon (b) Herbarium
(c) Key (d) Taxa
2. The arrangement of axonemal microtubules is referred to as the 1
(a) 9+1 array (b) 9+2 array
(c) 9+3 array (d) 9+4 array
3. The opening and closing of stomata is controlled by the 1
(a) amount of CO2 in atmosphere
(b) amount of O2 in atmosphere
(c) turgidity of guard cells
(d) number of guard cells
4. Necrosis or death of leaf tissue is a deficiency symptom of 1
(a) zinc (b) sulphur
(c) copper (d) iron
5. The factor responsible for apical dominance in most higher plants is 1
(a) auxin (b) cytokinin
(c) ethylene (d) abscisic acid
6. Define inflorescene. Mention the two major types of inflorescene. 2
7. What is ER? Name the different type of ER. 2
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8. What is chemiosmotic hypothesis? 2
9. What are the general characteristics of algae? 3
10. a. Differentiate between heartwood and sapwood.
Or 3
b. Write three points of differences between parenchyma tissue and
collenchyma tissue.
11. What is hydroponics? Write its two importance. 3
12. a. Describe the structure of nucleus with the help of a labelled diagram.
Or 5
b. Describe the structure of chloroplast with a neatly labelled diagram.
13. a. What is diffusion? Explain in detail the facilitated mode of diffusion in the
movement of substances in plants.
Or 5
b. Discuss the five recognized groups of plant growth regulators.
14. a. Explain the Calvin cycle with the help of schematic representation.
Or 5
b. Give the schematic representation of an overall view of citric acid cycle.
PART –B
1. Five kingdom classification was proposed by 1
(a) Aristotle (b) Linnaeus
(c) Darwin (d) R.H Whittaker
2. The largest phylum of Animalia is_____ 1
(a) Arthropoda (b) Annelida
(c) Mollusca (d) Aschelminthes
3. Which one of the following is not a pigment? 1
(a) Carotenoids (b) Chlorophyll
(c) Anthocyanin (d) Cellulose
4. The largest gland in the human body is 1
(a) pancreas (b) duodenum
(c) liver (d) gall bladder
5. The pineal gland secretes a hormone called 1
(a) melatonin (b) thyroxine
(c) calcitonin (d) growth hormone
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6. Write four characteristic features of the class Aves. 2
7. Name the four types of animal tissues. 2
8. Why is meiosis important? 2
9. Draw a neat labelled diagram of alimentary canal of cockroach. 3
10. a. How is respiration regulated? Explain briefly.
Or 3
b. Describe briefly the double circulatory system in human beings.
11. Explain in brief the mechanism of hearing. 3
12. a. What are the factors affecting enzyme action? Explain in brief.
Or 5
b. Why is mitosis known as equational division? Briefly explain the different
stages of mitosis.
13. a. Define cardiac cycle. Explain the various steps involved in cardiac cycle.
Or 5
b. Explain the internal structure of kidney.
14. a. Explain the mechanism of muscle contraction.
Or 5
b. Describe the mechanism of hormone action.
