CBSE Class 10 Science • Chapter Revision
How Do Organisms Reproduce Class 10 Worksheet with Answers
How does a single yeast cell produce a new individual? Why can a potato grow from a piece containing a bud? What happens after pollen reaches a flower’s stigma? Use the How Do Organisms Reproduce Class 10 worksheet with answers to revise reproduction through examples, comparisons and process-based questions.
Reproduction produces new individuals and supports the continuation of a species. This chapter connects DNA copying and variation with asexual reproduction, sexual reproduction in flowering plants, human reproductive systems and reproductive health.
Before attempting the worksheet, review our How Do Organisms Reproduce Class 10 notes and mind map . Attempt questions independently, then check the answers to improve scientific terms, diagram labels and the order of events in each process.
How Do Organisms Reproduce Class 10 Summary
Reproduction involves passing genetic information to offspring. Asexual reproduction occurs without the fusion of gametes, while sexual reproduction involves gamete fusion. The resulting offspring resemble their parents, but genetic differences can occur.
| Topic | What to understand | Practice focus |
|---|---|---|
| DNA copying and variation | Genetic information is copied and passed to offspring. | Explain similarity and variation. |
| Asexual reproduction | New individuals form without gamete fusion. | Match methods with organisms and describe stages. |
| Flowering plants | Pollination enables the events leading to fertilisation. | Flower labels, pollen tube growth and seed formation. |
| Human reproduction | Specialised organs produce gametes and support development. | Organ functions and process sequences. |
| Reproductive health | Knowledge supports informed decisions and disease prevention. | Distinguish contraception from protection against infections. |
Asexual Reproduction Class 10 Short Notes
Asexual reproduction usually involves one parent. Offspring are generally genetically very similar to that parent, although mutations can introduce differences. Different organisms use different methods depending on their body organisation.
| Method | Main process | Example |
|---|---|---|
| Binary fission | One cell divides into two daughter individuals. | Amoeba; Leishmania. |
| Multiple fission | One parent cell gives rise to several daughter individuals. | Plasmodium. |
| Budding | An outgrowth develops into a new individual. | Yeast; Hydra. |
| Fragmentation | A body breaks into fragments that grow into new individuals. | Spirogyra. |
| Spore formation | Spores disperse and grow under suitable conditions. | Rhizopus, a bread mould. |
| Vegetative propagation | New plants develop from vegetative parts. | Potato stem buds; Bryophyllum leaf buds. |
Regeneration and Fragmentation
Regeneration is the ability to restore lost or damaged parts. In organisms such as Planaria, specialised cells can allow body pieces to develop into complete individuals. However, regeneration does not always produce a new organism: repairing a wound is also regeneration.
Remember the Potato “Eye”
The eye of a potato is a bud on a modified stem called a tuber. A piece containing a suitable bud can develop into a new plant. The potato tuber is not a root.
Advantages of Vegetative Propagation
Vegetative propagation helps growers multiply plants with desirable characteristics. It is useful for many plants that do not produce viable seeds, and propagated plants may flower and fruit earlier than plants grown from seeds. Cuttings, layering and grafting are common artificial methods.
Sexual Reproduction in Flowering Plants
The stamen includes an anther and a filament. The anther produces pollen grains. The pistil includes the stigma, style and ovary; the ovary contains ovules, each containing an egg cell.
Pollination transfers pollen from an anther to a stigma. In self-pollination, this occurs within the same flower or between flowers of the same plant. Cross-pollination occurs between flowers on different plants of the same species.
From Pollination to Seed Formation
- A compatible pollen grain reaches the stigma.
- It germinates and forms a pollen tube through the style.
- The tube carries male gametes towards an ovule.
- A male gamete fuses with the egg, forming a zygote.
- The zygote develops into an embryo.
- The ovule develops into a seed, and the ovary usually develops into a fruit.
Human Reproductive Systems: Important Functions
Puberty involves hormonal changes and maturation of reproductive organs. The timing and pace of these changes vary between individuals. Learn the reproductive structures alongside their functions rather than memorising labels alone.
| Structure | Function |
|---|---|
| Testes | Produce sperm and the hormone testosterone. |
| Scrotum | Helps maintain a temperature suitable for sperm production. |
| Vas deferens | Transports sperm towards the urethra. |
| Seminal vesicles and prostate gland | Add fluids that contribute to semen and support sperm. |
| Ovaries | Produce egg cells and reproductive hormones. |
| Oviducts or fallopian tubes | Carry the egg; fertilisation usually occurs here. |
| Uterus | Supports implantation and development of the embryo and foetus. |
| Vagina | Receives sperm during intercourse and forms part of the birth canal. |
Fertilisation, Implantation and Placenta
Fertilisation is the fusion of a sperm and an egg to form a zygote. The dividing embryo travels towards the uterus and implants in its lining. The placenta provides an exchange surface through which nutrients and oxygen reach the developing baby and wastes pass towards the mother’s circulation. Maternal and foetal blood normally remain in separate circulations.
Why Does Menstruation Occur?
When pregnancy does not occur, hormonal changes lead to the shedding of the uterine lining. Blood and tissue leave through the vagina. Menstruation is a normal biological process, and cycle length can vary.
Reproductive Health Class 10 Revision
Contraceptive methods help prevent pregnancy through different mechanisms. Barrier methods, hormonal methods, intrauterine devices and surgical methods are broad categories studied in this chapter. Preventing pregnancy and reducing sexually transmitted infection risks are different functions.
Contraception and Infection Prevention
Condoms help reduce the risk of many sexually transmitted infections as well as pregnancy. Contraceptive pills and intrauterine devices do not provide protection against sexually transmitted infections.
How Do Organisms Reproduce Class 10 MCQs with Answers
1. Which organism commonly reproduces by budding?
A. Amoeba
B. Yeast
C. Plasmodium
D. Spirogyra
Answer: B. Yeast. A small bud develops on the parent cell and can separate into a new individual.
2. Which flower structure usually develops into the fruit?
A. Stigma
B. Anther
C. Ovary
D. Filament
Answer: C. Ovary. The ovary usually becomes the fruit, while ovules become seeds.
3. Where does fertilisation usually occur in humans?
A. Ovary
B. Fallopian tube
C. Uterus
D. Vagina
Answer: B. Fallopian tube. Implantation and further development occur in the uterus.
Assertion–Reason Practice
Assertion: Pollination and fertilisation are different processes.
Reason: Pollination is pollen transfer, while fertilisation involves the fusion of gametes.
Answer: Both statements are true, and the reason correctly explains the assertion.
How Do Organisms Reproduce Class 10 Case-Based Questions
Case Study: Growing Plants from Potato Pieces
A student plants two potato pieces in moist soil. One contains an eye, while the other has no bud. Under suitable conditions, the piece with the eye produces a shoot.
Question 1: Name the method of reproduction.
Vegetative propagation.
Question 2: What is the potato eye?
A bud on the potato tuber.
Question 3: Why is the bud important?
It contains growing tissue that can develop into a shoot.
Question 4: Does this method involve gamete fusion?
No. It is an asexual method of reproduction.
Important Questions and Diagram Practice
- Explain the role of DNA copying in reproduction.
- Compare binary fission and multiple fission with examples.
- Describe budding in Hydra using labelled stages.
- Distinguish fragmentation from regeneration.
- Explain vegetative propagation and its advantages.
- Compare pollination and fertilisation.
- Draw a flower and label its reproductive parts.
- Explain the functions of the testes, ovaries and uterus.
- Distinguish fertilisation from implantation.
- Describe the role of the placenta and explain menstruation.
How to Use the Worksheet as a Chapter Test
Attempt the worksheet without checking answers. Review mistakes under reproduction methods, plant processes, human organ functions or diagrams. For comparisons, write paired differences. For process questions, present the stages in the correct order.
Practise diagrams of binary fission, budding, a flower and the human reproductive systems. Keep label lines clear and explain the function of each important structure.
Frequently Asked Questions
Why is reproduction important if an individual can survive without it?
Reproduction creates new individuals and supports the continuation of a species across generations. It serves a different purpose from processes that maintain an individual’s life.
Are offspring produced asexually always completely identical?
They are generally genetically very similar, but mutations during DNA copying can create differences. Avoid describing them as invariably identical.
Does sexual reproduction always involve two separate parents?
Sexual reproduction involves gamete fusion. The gametes can come from two individuals, but self-fertilisation is possible in some organisms, including certain flowering plants.
Is regeneration always reproduction?
No. Regeneration can repair damaged tissues or replace a lost part. It produces new individuals only in certain organisms and circumstances.
How is budding different from binary fission?
Binary fission divides a parent into two daughter individuals. Budding produces a smaller outgrowth on the parent that develops into a new individual.
What is the difference between a pollen grain and a male gamete?
A pollen grain is a structure that produces and carries male gametes. It is not itself the male gamete that fuses with the egg.
What happens to the ovule and ovary after fertilisation?
The ovule develops into a seed, and the ovary usually develops into a fruit. The embryo develops within the seed.
How is implantation different from fertilisation?
Fertilisation forms a zygote through sperm–egg fusion. Implantation occurs later, when the developing embryo attaches to and embeds in the uterine lining.
Does an intrauterine device protect against sexually transmitted infections?
No. An intrauterine device prevents pregnancy but does not protect against sexually transmitted infections. Condoms help reduce transmission risks.
Where can I find related notes and a mind map?
Visit our How Do Organisms Reproduce Class 10 notes and mind map before returning to the worksheet to test your understanding.
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