MBOSE Class 11 Question Paper 2023 for Biology

Total No. of Printed Pages –– 7 (2)
SECTION – A1
2023
Choose and write the correct answer : 1  5=5
BIOLOGY
1. Which of the following is a modified root
( Theory )
(a) Potato
Full Marks : 70
(b) Sweet potato
Time : 3 hours
(c) Ginger

General Instructions : (d) Onion

This question paper consists of 5 (five) sections:

(i) Section A consists of two parts A1 and A2. 2. Water vascular system is present in animals belonging
to phylum
A1 consists of 5 (five) questions (Q1 – Q5) which are multiple
choice questions, of one mark each; should be answered (a) Arthropoda
together in one place.
(b) Annelida
A2 consists of 5 (five) questions (Q6 – Q10) of one mark
each, to be answered in one word or one sentence. (c) Mollusca

(ii) Section B consists of 7 (seven) questions (Q11 to Q17) of (d) Echinodermata
two marks; to be answered in approximately 20 – 30 words
each.
3. In Australian acacia, the leaves are modified into
(iii) Section C consists of 9 (nine) questions (Q18 – Q26) of
three marks each to be answered in 30 – 50 words each. (a) Spines

(iv) Section D consists of 1 (one) question (Q27) of 4 marks, to (b) Tendrils
be answered in approximately 70 – 100 words.
(c) Swollen, green petiole for synthesis of food.
(v) Section E consists of 3 (three) questions (Q28 to Q30) of 5
marks each, to be answered in approximately 80 – 120 words. (d) Pitcher.

HS/XI/Sc/Bio/23 HS/XI/Sc/Bio/23

(3) (4)

4. In which cell organelles synthesis of protein takes place SECTION – B

(a) Golgi complex ( Short answer – I ) 2  7 = 14
(b) Ribosomes
11. Why are bryophytes called as “Amphibians” of the
(c) Mitochondria 2
plant kingdom?
(d) Plastids
Or

5. The hormone secreted by pineal gland is Define Binomial Nomenclature. Give one example.
1+1=2
(a) Melanin
12. Why are Deuteromycetes called as “Imperfect fungi”? 2
(b) Melatonin
(c) Melanocytes
13. What are viruses? Who discovered virus? 1+1=2
(d) Calcitonin.

14. Draw a labelled diagram of a human heart. 2

SECTION – A2
15. Define biomacromolecules. Give an example. 1+1=2
( Very short answer ) 1  5=5

16. State the “Law of Limiting Factors”. 2
6. Where is the hunger centre located in the human brain? 1

7. What are pneumatophores? 1 17. Name the protective covering of the brain. 2

Or
8. Name the end product of Glycolysis. 1
Old people usually suffer from inflamed and stiff joints.
9. Which hormone acts as a stress hormone? 1 What is this condition called? State the reasons for
the symptoms. 1+1=2
10. Name the protein-rich layer found in Euglenoids. 1

HS/XI/Sc/Bio/23 HS/XI/Sc/Bio/23

(5) (6)

SECTION –– C 24. Give the importance of Liver, Lungs and Skin in
excretion. 3
( Short answer – II ) 3  9 = 27

25. Explain the mechanism of coagulation of blood. 3
18. On what criteria is the five kingdom classification of
organisms based? 3 26. Draw a labelled diagram of location of Endocrine glands
in human body. 3
Or
Mention the important characteristics of Gymnosperms. 3 Or

Why Pituitary gland is called as “Master gland”? 3
19. Describe the structure of mitochondria with the help
of a diagram. 2+1=3
SECTION – D

20. Differentiate between plant cells and animal cells. 3
27. Describe the mechanism of Urine formation in humans.
1+3=4
Or
21. Why photorespiration does not take place in C4 plants?
Explain. 3 Describe the different types of phyllotaxy with suitable
diagrams. 3+1=4

22. Explain the mechanism of enzyme action. 3
SECTION – E

( Long answer type )
23. Briefly describe the phases of growth with the help of
a growth curve. 2+1=3
28. Explain conduction of nerve impulse along a nerve
fibre. 5
Or
Or
Define inflorescence. Differentiate between the
racemose and cymose type of inflorescence. 1+2=3 Draw and explain the Tricarboxylic acid cycle (Kreb’s
cycle) 1+4=5

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(7)

29. Describe the process of digestion in Frogs with the
help of a diagram. 4+1=5
Or
Define muscle. Name the different type of muscles
based on their location. Differentiate between straited
muscle and Non-straited muscle. 1+1+3=5

30. Define mitosis. Describe the different phases of mitosis
with well labelled diagrams. ½ + 2½ + 2 = 5
Or
With a labelled diagram describe the internal
structures of a dorsiventral leaf. 1+4=5

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