---
title: "How do Organisms Reproduce?: CBSE Class 10 Science previous year questions"
url: https://www.swavid.com/cbse/class-10/science/pyq/how-do-organisms-reproduce
---

# How do Organisms Reproduce?: CBSE Class 10 Science previous year questions

18 questions from CBSE Class 10 board papers, newest first, each with full working.

## CBSE Class 10 Science Question Paper 2026 (Set 31/1/1) with Solutions

### Question 2

*1 mark · MCQ*

Identify the type of reproduction shown in the diagram given below :

- Budding
- Fragmentation
- Spore Formation
- Binary Fission

**Solution**

1. The diagram illustrates the splitting of a single-celled organism into two equal halves, which is characteristic of binary fission.
2. Budding involves a small outgrowth, while fragmentation involves breaking into pieces.

**Answer:** (d) Binary Fission

> Common mistake: Confusing binary fission with multiple fission or budding.

### Question 3

*1 mark · MCQ*

Identify the correct statement for spirogyra, leishmania and hydra :

- they reproduce sexually.
- they are unicellular.
- they are multicellular.
- they reproduce asexually.

**Solution**

1. Spirogyra (alga), Leishmania (protozoan), and Hydra (coelenterate) all reproduce primarily through asexual methods such as fragmentation, binary fission, and budding respectively.
2. Therefore, the common correct statement is that they reproduce asexually.

**Answer:** (d) they reproduce asexually.

> Common mistake: Assuming all three share the same cellular structure.

### Question 11 (OR)

*2 marks · Short answer*

State two differences between pollination and fertilization.

**Solution**

1. Pollination is the transfer of pollen grains from the anther to the stigma of a flower, whereas fertilization is the fusion of the male gamete with the female gamete.
2. Pollination is an external process aided by agents like wind, water, or insects, while fertilization is an internal cellular process occurring inside the ovule.

**Answer:** Pollination is the transfer of pollen to the stigma, while fertilization is the fusion of male and female gametes.

> Common mistake: Stating that pollination leads directly to seed formation without mentioning fertilization.

### Question 12

*2 marks · Short answer*

Draw a neat diagram to show germination of pollen on the female reproductive part of the flower. Name and label only the following parts :
(a) The part that receives the pollen grain.
(b) The structure that carries the male germ cell to reach the female germ cell.

**Part (a)**

1. The part that receives the pollen grain is the stigma.

Answer (a): Stigma

**Part (b)**

1. The structure that carries the male germ cell to reach the female germ cell is the pollen tube.

Answer (b): Pollen tube

**Answer:** Diagram: Draw a longitudinal section of a carpel showing the stigma, style, and ovary. Show pollen grains on the stigma with pollen tubes growing down through the style into the ovary. Label (a) Stigma as the part receiving pollen and (b) Pollen tube as the structure carrying the male germ cell.

> Common mistake: Confusing the style with the pollen tube.

### Question 16

*5 marks · Case-based*

Given below are certain situations. Analyse each and describe its possible impact :
(i) A population of bacteria living in temperate waters whose temperature increased by global warming.
(ii) The sperm encounters the egg when it reaches the oviduct in human females.
(iii) Self pollination does not occur in a flower that contains only pistil.
(iv) Egg does not get fertilised in a human female.
(v) When the seed is placed under appropriate condition of water and air in the soil ?

**Part (i)**

1. The bacteria will likely die as they are adapted to temperate conditions and cannot survive the heat.

Answer (i): The population will decline or die out.

**Part (ii)**

1. Fertilisation will occur, leading to the formation of a zygote.

Answer (ii): Fertilisation occurs.

**Part (iii)**

1. Cross-pollination must occur for reproduction to take place.

Answer (iii): Cross-pollination is required.

**Part (iv)**

1. The thickened uterine lining will break down, resulting in menstruation.

Answer (iv): Menstruation occurs.

**Part (v)**

1. The seed will germinate and develop into a seedling.

Answer (v): Germination occurs.

**Answer:** Analysis of biological situations.

> Common mistake: Confusing fertilisation with implantation.

### Question 16 (OR)

*5 marks · Case-based*

Given below are certain situations. Analyse and describe what would happen when :
(i) Spores are liberated from blob-like structures of the bread mould ?
(ii) Leaves of bryophyllum fall on wet soil ?
(iii) A pollen from different species land on the stigma of totally unrelated species ?
(iv) Copper-T is placed in the uterus of a human female ?
(v) Spirogyra breaks into smaller fragments upon maturation ?

**Part (i)**

1. Spores are covered by thick walls that protect them until they come into contact with another moist surface and begin to grow.
2. Under favourable conditions, they germinate and develop into new Rhizopus individuals.

Answer (i): Spores germinate under favourable moist conditions to develop into new bread mould individuals.

**Part (ii)**

1. Leaves of Bryophyllum have buds in the notches along the leaf margin.
2. When these leaves fall on wet soil, the buds develop into new plants.

Answer (ii): Buds present in the leaf notches develop into new Bryophyllum plants.

**Part (iii)**

1. Pollen grain from a different species is not compatible with the stigma of an unrelated species.
2. No pollen germination or pollen tube growth takes place, preventing fertilization.

Answer (iii): Pollen fails to germinate and no fertilization takes place.

**Part (iv)**

1. Copper-T is a contraceptive device placed in the uterus.
2. It prevents implantation of the fertilized egg in the uterus.

Answer (iv): It prevents implantation in the uterus, acting as a method of contraception.

**Part (v)**

1. Spirogyra is a simple multicellular organism that undergoes fragmentation upon maturation.
2. Each fragment grows into a new individual.

Answer (v): Each fragment grows into a new Spirogyra individual.

**Answer:** Described the outcomes of the five biological situations based on NCERT Class 10 Science.

> Common mistake: Confusing the function of Copper-T with barrier methods that prevent fertilization instead of implantation.

## CBSE Class 10 Science Question Paper 2025 (Set 31/1/1) with Solutions

### Question 10

*1 mark · MCQ*

The correct/true statement(s) for a bisexual flower is/are :
(i) They possess both stamen and pistil.
(ii) They possess either stamen or pistil.
(iii) They exhibit either self-pollination or cross-pollination.
(iv) They cannot produce fruits on their own.

- (i) only
- (iv) only
- (i) and (iii)
- (i) and (iv)

**Solution**

1. A bisexual flower possesses both male (stamen) and female (pistil) reproductive organs.
2. Due to the presence of both organs, they can exhibit self-pollination or cross-pollination.

**Answer:** (c) (i) and (iii)

> Common mistake: Confusing bisexual flowers with unisexual flowers which lack one of the reproductive whorls.

### Question 22

*2 marks · Very short answer*

Draw labelled diagrams to show different stages of budding in Hydra.

**Solution**

1. Draw a diagram showing a parent Hydra with a small outgrowth called a bud.
2. Draw subsequent stages showing the growth of the bud, development of tentacles, and finally its detachment from the parent body.

**Answer:** Labeled diagram showing parent Hydra, developing bud, tentacles, and new independent Hydra.

> Common mistake: Not labeling the bud and tentacles clearly.

### Question 35

*5 marks · Long answer*

(a) (i) Write the functions of the following parts of human female reproductive system :
(I) Ovary
(II) Fallopian tube
(III) Uterus
(ii) State briefly two contraceptive methods used by human males.

**Part (a) (i)**

1. (I) Ovary: Produces female gametes (ova/eggs) and secretes female hormones (oestrogen and progesterone).
2. (II) Fallopian tube: Carries the egg from the ovary to the uterus and is the site of fertilisation.
3. (III) Uterus: Site of implantation of the fertilized egg, and nourishes the developing embryo.

Answer (a) (i): Functions of ovary, fallopian tube, and uterus stated.

**Part (a) (ii)**

1. Condoms: Used over the penis as a mechanical barrier to prevent sperm from reaching the vagina.
2. Vasectomy: Surgical method in males where the vas deferens is blocked to prevent sperm transfer.

Answer (a) (ii): Condoms and vasectomy.

**Answer:** Functions of ovary, fallopian tube, uterus, and two male contraceptive methods.

> Common mistake: Confusing the site of fertilization (fallopian tube) with the site of implantation (uterus).

### Question 35 (OR)

*5 marks · Long answer*

(b) (i) Differentiate between self-pollination and cross-pollination.
(ii) Identify A, B and C in the diagram given below and write one function of each.

**Part (b) (i)**

1. Self-pollination: Transfer of pollen grains from the anther to the stigma of the same flower or another flower of the same plant.
2. Cross-pollination: Transfer of pollen grains from the anther of one flower to the stigma of another flower of a different plant of the same species.

Answer (b) (i): Definitions of self-pollination and cross-pollination.

**Part (b) (ii)**

1. A: Stigma / Pollen grain - Receives the pollen grain and provides surface for germination.
2. B: Pollen tube - Grows down through the style to carry male gametes to the ovary.
3. C: Female gamete / Ovule - Contains the egg cell which fuses with the male gamete during fertilization.

Answer (b) (ii): A: Stigma/Pollen grain, B: Pollen tube, C: Female gamete/Ovule with functions.

**Answer:** Difference between self and cross pollination, and identification of A, B, C with functions.

> Common mistake: Confusing pollen tube function with the style.

## CBSE Class 10 Science Question Paper 2024 (Set 31/1/1) with Solutions

### Question 16

*1 mark · MCQ*

In which of the following organisms, multiple fission is a means of asexual reproduction ?

- Yeast
- Leishmania
- Paramoecium
- Plasmodium

**Solution**

1. Plasmodium, the malaria parasite, divides into many daughter cells simultaneously by multiple fission.
2. Yeast reproduces by budding, Leishmania by binary fission, and Paramoecium also by binary fission.

**Answer:** (d) Plasmodium

> Common mistake: Confusing multiple fission in Plasmodium with binary fission in Amoeba or Leishmania.

### Question 35

*5 marks · Long answer*

(A) (i) Name three techniques/devices used by human females to avoid pregnancy. Mention the side effects caused by each.
(ii) What will happen if in a human female (a) fertilisation takes place, (b) an egg is not fertilised ?

**Part (i)**

1. Three contraceptive techniques are: (1) Barrier methods (e.g., condoms), (2) Oral pills (hormonal pills), and (3) Intrauterine contraceptive devices (IUDs like Copper-T).
2. Side effects: Barrier methods have negligible side effects; oral pills can cause hormonal imbalance and related health issues; IUDs can cause side effects due to uterine irritation or infection if not monitored.

Answer (i): Barrier methods (low side effects), oral pills (hormonal imbalance), IUDs (uterine irritation/infection).

**Part (ii)**

1. (a) If fertilisation takes place, the zygote gets implanted in the lining of the uterus, leading to pregnancy, and menstruation stops.
2. (b) If the egg is not fertilised, the uterine lining thickens and then breaks down, leading to menstruation.

Answer (ii): (a) Pregnancy occurs; (b) Menstruation occurs.

**Answer:** Contraceptive methods with side effects and consequences of fertilisation or non-fertilisation explained.

> Common mistake: Listing methods of contraception without specifying their respective side effects.

### Question 35 (OR)

*5 marks · Long answer*

(B) (i) Draw a diagram showing spore formation in Rhizopus and label the (a) reproductive and (b) non-reproductive parts. Why does Rhizopus not multiply on a dry slice of bread ?
(ii) Name and explain the process by which reproduction takes place in Hydra.

**Part (i)**

1. Diagram: Draw sporangium showing tiny blob-like structures (sporangia) on thread-like structures (hyphae). Label (a) reproductive part as sporangium (containing spores) and (b) non-reproductive part as hyphae/stolon.
2. Rhizopus does not multiply on a dry slice of bread because spores require moisture and nutrients to germinate and grow, which are absent in dry conditions.

Answer (i): Sporangium is the reproductive part, hyphae are non-reproductive; lacks moisture on dry bread.

**Part (ii)**

1. Hydra reproduces by budding, which is an asexual mode of reproduction.
2. A bud develops as an outgrowth due to repeated cell division at a specific site, grows into a tiny individual, and detaches from the parent body to live independently.

Answer (ii): Budding: a bud grows and detaches from the parent Hydra.

**Answer:** Rhizopus spore formation details, lack of moisture on dry bread, and budding in Hydra explained.

> Common mistake: Failing to mention the requirement of moisture for spore germination in fungi.

## CBSE Class 10 Science Question Paper 2023 (Set 31/1/1) with Solutions

### Question 12

*1 mark · MCQ*

Select the INCORRECT match (between the plant and its vegetative part) from the following :

- Bryophyllum, leaf
- Potato, stem
- Money-plant, stem
- Rose, root

**Solution**

1. Rose plants are artificially propagated primarily through stem cuttings, not roots.
2. Bryophyllum propagates through leaves, potato through tubers (stems), and money-plant through stems, making the match for Rose incorrect.

**Answer:** (d) Rose, root

> Common mistake: Assuming all plants reproduce vegetatively through roots.

### Question 35

*5 marks · Long answer*

(a) Name the parts of a bisexual flower that are not directly involved in reproduction.
(b) Differentiate between self pollination and cross pollination. List any two significance of pollination.
(c) What is the fate of ovules and ovary after fertilization in a flower?

**Part (a)**

1. The non-essential whorls of a bisexual flower that are not directly involved in reproduction are sepals (calyx) and petals (corolla).

Answer (a): Sepals and petals.

**Part (b)**

1. Self-pollination is the transfer of pollen grains from the anther to the stigma of the same flower or another flower of the same plant, whereas cross-pollination is the transfer of pollen from the anther of one flower to the stigma of another flower of a different plant of the same species.
2. Significance of pollination: (1) It brings male and female gametes together for fertilization. (2) It leads to the formation of seeds and fruits, ensuring continuity of species.

Answer (b): Self-pollination occurs within the same plant; cross-pollination occurs between different plants. Significance: fertilization and seed formation.

**Part (c)**

1. After fertilization, the ovules develop into seeds and the ovary ripens and develops into a fruit.

Answer (c): Ovules develop into seeds and the ovary develops into a fruit.

**Answer:** Answered plant reproduction parts, differences between pollination types, and post-fertilization changes.

> Common mistake: Confusing the fate of ovary and ovule after fertilization.

## CBSE Class 10 Science Question Paper 2022 (Set 31/1/1) with Solutions

### Question 3

*2 marks · Short answer*

(a) Which of the following flowers will have higher possibility of self-pollination ?
 Mustard, Papaya, Watermelon, Hibiscus
(b) List the two reproductive parts of a bisexual flower.

**Part (a)**

1. Hibiscus is a bisexual flower containing both male and reproductive organs, giving a high possibility of self-pollination.

Answer (a): Hibiscus

**Part (b)**

1. The male reproductive part is the stamen (anther and filament).
2. The female reproductive part is the pistil or carpel (stigma, style, and ovary).

Answer (b): Stamen and pistil

**Answer:** Hibiscus has a higher possibility of self-pollination, and the two reproductive parts of a bisexual flower are stamen and pistil.

> Common mistake: Naming unisexual flowers like papaya or watermelon for self-pollination.

### Question 4

*2 marks · Short answer*

Which one of the two multicellular organisms — Spirogyra and Planaria reproduces by regeneration and why ? Give an example of any other organism which can also reproduce by the same process.

**Solution**

1. Planaria reproduces by regeneration because its body can be cut into pieces and each piece grows into a complete organism through specialized cells.
2. These specialized cells proliferate and make large numbers of cells, undergoing differentiation to form various tissues and organs.
3. An example of another organism that reproduces by regeneration is Hydra.

**Answer:** Planaria reproduces by regeneration using specialized cells that proliferate and differentiate; Hydra is another example.

> Common mistake: Confusing fragmentation in Spirogyra with true regeneration in Planaria.

### Question 10

*3 marks · Short answer*

(a) Mention one function each of the following organs in human male reproductive system :
(i) Testis
(ii) Scrotum
(iii) Vas deferens
(iv) Prostate gland
(b) Name the type of germ cell which (i) is motile, and (ii) stores food.

**Part (a)**

1. (i) Testis: Produces male germ cells (sperms) and the hormone testosterone.
2. (ii) Scrotum: Provides a lower temperature than body temperature required for sperm production.
3. (iii) Vas deferens: Delivers the sperms from the testis to the urethra.
4. (iv) Prostate gland: Secretes fluid that makes the transport of sperms easier and provides nutrition.

Answer (a): Functions of testis, scrotum, vas deferens, and prostate gland stated.

**Part (b)**

1. (i) The male germ cell (sperm) is motile.
2. (ii) The female germ cell (egg/ovum) stores food.

Answer (b): (i) Sperm (ii) Ovum

**Answer:** (a) (i) Testis: Produce sperms and testosterone. (ii) Scrotum: Provides lower temperature for sperm formation. (iii) Vas deferens: Transfers sperms. (iv) Prostate gland: Secretes fluid to nourish and ease sperm transport. (b) (i) Sperm, (ii) Egg/Ovum.

> Common mistake: Confusing the functions of male and female reproductive organs.

## Related pages

- [How do Organisms Reproduce?: NCERT solutions](https://www.swavid.com/science/class/10/chapter/how-do-organisms-reproduce/ncert-solutions)
- [All CBSE Class 10 Science papers](https://www.swavid.com/cbse/class-10/science/previous-year-papers)

Solutions written by SwaVid, a personal AI tutor for Class 6 to 10 Maths and Science. Practise this chapter free: https://www.swavid.com/start/student