DELHI PUBLIC SCHOOL ,

NAVI MUMBAI
HALF YEARLY EXAMINATION (2025-2026)
SAMPLE PAPER
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Class: XI M. marks: 70
Subject: Biology (044) Duration:3Hours.
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General Instructions : This Question paper carries 33 questions and 5 printed pages.

(i) The question paper has five sections and 33 questions. All questions are compulsory.
(ii) Section–A has 16 questions of 1 mark each; Section–B has 5 questions of 2 marks each;
Section– C has 7 questions of 3 marks each; Section– D has 2 case-based questions of 4
marks each; and Section–E has 3 questions of 5 marks each.
(iii) There is no overall choice. However, internal choices have been provided in some
questions. A student has to attempt only one of the alternatives in such questions.
(iv) Wherever necessary, neat and properly labeled diagrams should be drawn.

SECTION A

1. In hierarchy of classification order is present between 1

(a) family and genus (b) family and species (c) family and class (d) Phylum and kingdom

2. Naked cytoplasm, multinucleated and saprophytic are the characteristics of: 1

a) Monera (b) Protista (c) Fungi (d) Slime moulds

3. Match the following and choose the correct options. 1

Column I Column II
A. Physalia i. Sea anemone
B. Meandrina ii. Sea fan
C. Gorgonia iii. Brain coral
D. Adamsia iv. Portuguese man-of-war

(a) A-iii, B-ii, C-i, D-iv (b)A-iv, B-ii, C-iii, D-i

(c)A-iv, B-iii, C-ii, D-I (d)A-ii, B-iii, C-i, D-iv

4. Which among the following is a triangular structure which joins the right atrium of the frog’s
heart and receives blood through the major veins called vena cava.

a)conusarteriosus b) sinus venosus c)atrio ventricular septum d)Sino atrial node

5. Male frog can be distinguished from female frog by the presence of 1

(a) vocal sacs and copulatory pad on the first digit of the forelimb
(b) a neck and tail is absent
(c) the hindlimb ends in the five digits
(d) eyes are bulged and covered by the nictitating membrane
6.Which of the following statements are true about endoplasmic reticulum? 1
I. Smooth Endoplasmic Reticulum (SER) makes lipids.
II. It is also called the control centre of the cell.
III. It processes carbohydrates.
IV. It modifies chemicals that are toxic to the cell.
Choose the correct option. (a) I, II and III (b) I, III and IV
(c) I and IV (d) All of these

7. The cell theory, jointly given by Schleiden and Schwann did not explain 1
(a) all living organisms are composed of cells and their products
(b) cell is the structural and functional unit of living organisms
(c) formation of new cells
(d) None of the above

8. Which one of the following statement is correct? 1

(a) Slime moulds are autotrophic protists. (b) Protozoans lack cell wall.
(c) Dinoflagellates are immotile. (d) Pellicle is absent in Euglena.
9. Antheridia and archegonia are born on _____ in bryophytes 1
A. Sporophyte B. Gametophyte C. Both of these D. None of these

10. Water vascular system is the characteristic of which group of the following: 1

(a) Porifera (b) Ctenophora (c) Echinodermata (d) Chordata

11. Vexillary aestivation is found in the following: 1

a) Chinarose b) Gulmohar c) Calotropis d) Bean flowers

12.In case of poriferans, the spongocoel is lined with flagellated cells called : 1

a) Ostia b) Oscula c) Choanocytes d) Mesenchymal cells

Question No.13 to 16 consist of two statements – Assertion (A) and Reason (R).
Answer these questions selecting the appropriate option given below:
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are true and Reason is not correct explanation of Assertion.
(c) Assertion is true but Reason is false. (d) Assertion is false but Reason is true.

13. Assertion (A) Aschelminthes are called as pseudocoelomates. 1

Reason (R) In Aschelminthes, mesoderm is present as scattered pouches in
between ectoderm and endoderm.

14. Assertion (A) There is hepatic portal system in frog. 1

Reason (R) It is venous connection between liver and intestine in frog.
15. Assertion (A) In mitosis, two identical cells are produced from a single cell and karyokinesis
is followed by cytokinesis. 1
Reason (R) Cytokinesis is of two types, i.e. by cell-furrow method and cell-plate method.

16. Assertion (A) Mitochondria and chloroplast are semiautonomous organelles. 1

Reason (R) These are formed by the division of pre-existing organelles as well as they
contain DNA, but lack protein synthesising machinery.
SECTION B

17. The following statements describe the four main stages in the process of mitosis. 2
I. The spindle fibres breakdown and the nuclear membrane forms.
II. The chromosomes arrange themselves on the equator of the cell.
III. The spindle forms and the nuclear membrane disintegrates.
IV. The centromere splits and the sister chromatids migrate to the opposite poles of the cell.

Write the correct sequence of the stages in mitosis and also name the each stage.

18.a. Which type of sexual reproduction takes place in Volvox and Fucus? 2
b. What is the source of and use of ‘Agar’?
OR
Distinguish between the special roots of Cycas and Pinus

19. To which phylum/ class these terms are associated with? Write two more exclusive features
of these phylum/class. 2

a. Radula c. Parapodia
b. Combplates d. Placoid scales

20. Explain the basis for the different types inflorescence in flowering plants. 2

21. Name the classes of Fungi other than the imperfect fungi and phycomycetes. Make a table to
distinguish between these classes based on the structure of hyphae and fruiting bodies. 2

SECTION C

22. Mention the ploidy of the following: 3

protonemal cell of a moss, leaf cell of a moss;
prothallus cell of a ferm, gemma cell in Marchantia;
ovum of a liverwort, zygote of a fern.

23. What are Protochordates? Differentiate between Chordates and non-chordates by giving
five points. 3
OR
Differentiate between the following by giving two exclusive points
a. Platyhelminthes and Aschelminthes b.Arthropoda and Annelida
c.Amphibians and Reptiles
24. Give diagrams and one example each of the following 3
a. Hypogynous flower b. Free central placentation c. Imbricate aestivation

25. Distinguish between Osteichthyes and Chondrichthyes 3

26

3
27. Explain any three types of placentation with proper diagrams and their examples. 3

28. How is metagenesis exhibited in Cnidarians? Give an example and explain. 3

SECTION D
29. Observe the diagram given below and answer the following questions. 4

(i) Which of the following pair is correct?

(a) A—Fat bodies (b) C—Kidney (c) B—Ovary (d) E—Cloaca

(ii) In frog, the oviduct from ovary opens into

(a) cloaca (b) cloacal aperture (c) ureter (d) urinary bladder

(iii) How many eggs a female frog ovaries release at a time?

(a) 200 –300 (b) 2500 –3000 (c) 3000 –4000 (d) 1500

(iv) The tadpole respires through

(a) lungs (b) skin (c) gills (d) Both (a) and (b)
OR
(iv) In female frogs,
(a) ovaries are absent (b) ovaries are functionally connected with kidneys
(c) ovaries are not connected with kidney functionally
(d) ovaries and oviducts are rudimentary short
30. Phycomycetes – Members of phycomycetes are found in aquatic habitats and on decaying
wood in moist and damp places or as obligate parasites on plants. The mycelium is aseptate and
coenocytic. Asexual reproduction takes place by zoospores or by aplanospores .

Ascomycetes – Commonly known as sac-fungi, the ascomycetes are mostly multicellular, e.g.,
Penicillium, or rarely unicellular, e.g., yeast (Saccharomyces). They are saprophytic,
decomposers, parasitic or coprophilous (growing on dung). Mycelium is branched and septate

Basidiomycetes –Commonly known forms of basidiomycetes are mushrooms, bracket fungi or

puffballs. They grow in soil, on logs and tree stumps and in living plant bodies as parasites, e.g.,
rusts and smuts. The mycelium is branched and septate. The asexual spores are generally not
found, but vegetative reproduction by fragmentation is common. The sex organs are absent, but
plasmogamy is brought about by fusion of two vegetative or somatic cells of different strains or
genotypes. The resultant structure is dikaryotic (rust fungus).
(1) To whichclass the bread mould fungi belongs to ?
(2) What is the difference between zoospores and aplanospores?
(3) What is meant by anisogamous gametes?
(4) How is a dikaryon formed?
OR
(4) Give reason – Why ascomycetes are termed as sac fungi?

SECTION E

31. Give the floral formula of the family Solanaceae. Explain every symbol of this formula. 5
State the economic importance of some plants of this family by citing proper examples.

OR
After studying the detailed structure of cell membrane and after the discovery of electrons
microscope. It was revealed from chemical studies that cell membrane is a lipid bilayer
structure with integral and peripheral proteins. After that it was also concluded that cell
membrane also contain some amount of carbohydrate unit.
(i) What do you mean by the bilayer of cell membrane made up of lipids?
(ii) What are peripheral and integral proteins?
(iii) Draw a well labelled diagram of cell membrane.

32.A .The following diagrams show the position of floral parts on the thalamus.
(a) Identify the type of flowers A and B. Give an example of each.
(b) Mention the nature of the ovary in each case.

B.Aestivation refers to the arrangement of sepals or petals in relation to one another in the bud
condition. Three different types of aestivation (A, B, C) are given below.

Identify the types of aestivation and give an example of each.

33. What are the various stages of meiotic prophase-I? Enumerate the chromosome events
during each stage. 5
OR
1.A.What is a mesosome?State its various functions.

B. What do you mean by plasmids? What role do they play in bacteria?

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