Table of Contents
NCERT Solutions for Class 10 Science Chapter 8, titled ‘How do Organisms Reproduce,’ are invaluable resources for students preparing for their CBSE Term II exams. These NCERT solutions offer comprehensive answers to the questions in the NCERT textbook, allowing students to cross-check their responses against the provided samples. Chapter 8 of the NCERT Solutions for Class 10 Science, ‘How Do Organisms Work?’ focuses on the fascinating topic of reproduction.
The solutions for this chapter are meticulously prepared by experienced experts, ensuring students gain a clear understanding of the subject matter. By utilizing these NCERT Solutions for Class 10, students can enhance their knowledge and boost their confidence as they prepare for their exams.
NCERT Solutions Class 10 Science Chapter 8 How do Organisms Reproduce Free PDF Download
QUESTIONS (Page No. 128)
1. What is the importance of DNA copying in reproduction?
Answer:
i) DNA has the information required for the cell divisions and for the inheritance of features.
ii) Cell division (mitosis) occurs after DNA copying (DNA replication).
iii) Cell divisions are essential for the production of gametes (meiosis) and for the development of new individual from the zygote (mitosis).
iv) Hence, DNA copying is essential in reproduction.
(Or)
The consistency of DNA copying during reproduction is important for the maintenance of body design features that allow the organism to use that particular niche.
Also Check: CBSE Syllabus for Class 10
2. Why is variation beneficial to the species but not necessarily for the individual ?
Answer:
i) Variation is beneficial to the species but not necessarily for the individual because sometimes variation in an individual may results in death of that individuals.
ii) For example, if there is population of certain bacteria living in normal climatic conditions and the temperature increases due to global warming, then most of the bacteria will not be able to tolerate excessive heat and hence die.
iii) But some bacteria which had variations to resist heat would survive and grow further.
iv) Hence, we can say that variation is beneficial to the species but not necessarily for the individual.
Class 10 Science Chapter 8 How do Organisms Reproduce
QUESTIONS (Page No. 133)
1. How does binary fission differ from multiple fission?
Answer:
| BINARY FISSION | MULTIPLE FISSION |
| i) In this, parental cell divides and produces two daughter cells. | i) In this, a parental cell divides and produces more than two daughter cells. |
| ii) The parental nucleus divides into two daughter nuclei. | ii) The parental nucleus divides into many nuclei. |
| iii) It occurs during favourable conditions. Eg : Amoeba, Bacteria, etc. | iii) It occurs during unfavourable conditions. Eg: Plasmodium, Chlamydomonas etc. |
2. How will an organism be benefited if it reproduces through spores?
Answer
i) Spores are light in weight and get distributed easily to distant places by wind. This helps to avoid competition at one place.
ii) Spores are produced in large numbers, so that large number of organisms are produced.
iii) Spores are covered by protective coat, so that they remain dormant till favourable conditions.
3. Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration?
Answer:
i) Regeneration is carried out by specialised cells.
ii) Complex organisms do not have specialised cells and they have highly differentiated tissues.
iii) Hence, they cannot give rise to new individuals through regeneration.
4. Why is vegetative propagation practiced for growing some types of plants?
Answer:
Ans. Vegetative propagation is practiced for growing some types of plants because:
i) it is more rapid, easier and cheaper method.
ii) by this method good quality and variety of plants can be produced.
iii) it helps to introduce plants, in new areas where the seed germination fails to produce mature plant due to changes in environmental factors and the soil.
iv) it is used to grow a plant in which viable seeds are not formed or very few seeds are produced.
5. Why is DNA copying an essential part of the process of reproduction?
Ans. DNA copying, also known as DNA replication, is a crucial part of the reproduction process for several important reasons:
- Passing Genetic Information: DNA carries genetic instructions that determine the traits and characteristics of an organism. During reproduction, it’s vital to pass on this genetic information to the offspring accurately. DNA replication ensures that an identical copy of the genetic material is created, which will be inherited by the new organism.
- Maintaining Genetic Continuity: DNA copying ensures that the genetic information remains consistent from one generation to the next. This continuity is essential for the preservation of species and the transmission of traits from parents to offspring.
- Variation: While DNA replication creates an identical copy, there can be occasional errors or mutations in the process. These mutations can lead to genetic variations, which are essential for the evolution and adaptation of species over time.
Class 10 Science Chapter 8 How do Organisms Reproduce
QUESTIONS (Page No. 140) How is the process of pollination different from fertilization?
Answer:
| POLLINATION | FERTILIZATION |
| i) It is the process of transfer of pollen grains from anther to stigma. | i) It is the process of fusion of male gamete with female gamete. |
| ii) It occurs in plants. | ii) It occurs in sexually reproducing organisms. |
| iii) It results in fertilization. | iii) It results in the formation of zygote. |
2. What is the role of the seminal vesicles and the prostate gland ?
Answer:
Seminal vesicles and prostate gland help in:
i) secreting the nutritive fluids.
ii) transportation of sperms.
iii) providing nutrients to the sperms.
10. What are the changes seen in girls at the time of puberty?
Answer:
i) Increase in breast size and darkening of skin of the nipples present at the tips of the breasts.
ii) Appearance of hair in the genital area.
iii) Appearance of hair in other areas of skin like underarms, hands and legs.
iv) Increase in the size of uterus and ovary.
v) Beginning of menstrual cycle.
vi) More secretion of oil from the skin, which results in the appearance of pimples.
11. How does the embryo gets nourishment inside the mother’s body?
Answer:
i) The embryo gets nutrients from the mother’s blood with the help of a special tissue called placenta.
ii) Placenta is a disc which is embedded in the uterine wall.
iii) It connects villi on the embryo’s side of the tissue.
iv) On the mother’s side are blood spaces, which surround the villi.
v) This provides a large surface area for glucose and oxygen to pass from the mother to the embryo.
12. If a woman is using a copper T, will it help in protecting her from sexually transmitted diseases?
Answer:
No, a copper T (also known as an intrauterine device or IUD) does not provide protection against sexually transmitted diseases (STDs). The primary function of a copper T is to prevent pregnancy by creating a hostile environment for sperm inside the uterus. It does not offer any barrier or protection against infections that are transmitted through sexual contact.
Also Check: NCERT Solutions for Class 10 Science
- Chapter 1 – Equations and Chemical reactions
- Chapter 2 – Acids, Bases, and salt
- Chapter 3 – Non Metals and Metals
- Chapter 4 – Carbon and Its Compounds
- Chapter 5 – Periodic Classification Of Elements
- Chapter 6 – Life Processes
- Chapter 7 – Control and Coordination
- Chapter 8 – How do Organisms Reproduce?
- Chapter 9 – Heredity and Evolution
- Chapter 10 – Light Reflection and Refraction
- Chapter 11 – The Human Eye and Colorful World
- Chapter 12 – Electricity
- Chapter 13 – Magnetic Effects of Electric Current
- Chapter 14 – Sources of Energy
- Chapter 15 – Our Environment
- Chapter 16 – Sustainable Management of Natural Resources
Class 10 Science Chapter 8 How do Organisms Reproduce
EXERCISES (Page No. 141)
1. Asexual reproduction takes place through budding in
- amoeba.
- yeast.
- plasmodium.
- leishmania.
Answer: b. Yeast.
Asexual reproduction through budding is a common method in yeast, where a small bud or outgrowth forms on the parent cell and eventually separates to become a new individual.
2. Which of the following is not a part of the female reproductive system in human
beings?
- Ovary
- Uterus
- Vas deferens
- Fallopian tube
Answer: c. Vas deferens.
The vas deferens is a part of the male reproductive system. It is a duct that carries sperm from the testes to the urethra and is not present in the female reproductive system.
3. The anther contains
- sepals.
- ovules.
- carpel.
- pollen grains.
Answer: d. Pollen grains.
The anther is the part of the flower’s stamen, and it contains pollen grains. Pollen grains are essential for the process of pollination, which is crucial for plant reproduction.
4. What are the advantages of sexual reproduction over asexual reproduction?
Answer:
i) Sexual reproduction provides more chance for genetic variation.
ii) It plays an important role in origin of new species.
iii) It ensures the survival of species in a population.
5. Why does menstruation occur?
Answer: Menstruation occurs to break the lining of the uterus (gradually) so that it comes out through the vagina as blood and mucous. This happens if ovum is not fertilized.
6. Draw a labelled diagram of the longitudinal section of a flower.
Answer:
7. What are the different methods of contraception?
Answer: The contraceptive methods can be broadly divided into the following types:
i) Natural method : In this method, the sexual act is avoided from day 10 to 17 of the menstrual cycle because during this period, ovulation is expected and therefore, the chances of fertilization are very high.
ii) Barrier method : In this method, barriers (devices) are used to prevent the entry of sperms into female genital tract during sexual intercourse.
Eg: Condoms, diaphragm and cervical cap, copper-T or loop, etc.
iii) Chemical method : In this method, specific drugs are used by females to kill the sperms.
Eg: Vaginal pills, creams, jellies, etc.
iv) Surgical method : It includes vasectomy (blocking of vas deferens) in males, tubectomy (blocking of fallopian tubes) in females.
v) Hormonal method : In this, production of ovum is suppressed by changing the hormonal balance. Eg : Oral pills, i pill, etc.
8. How does reproduction help in providing stability to populations of species ?
Answer:
i) Reproduction plays role in producing the new individuals of the species that resembles the parents.
ii) Reproduction helps in continuation of the race.
iii) Reproduction replaces the individuals that are dead.
iv) Reproduction introduces new varieties.
v) Hence, reproduction helps in providing stability to populations of species.
9. How are the modes for reproduction different in unicellular and multicellular organisms?
Answer:
| REPRODUCTION IN UNICELLULAR ORGANISMS | REPRODUCTION IN MULTICELLULAR ORGANISMS |
| Mode of reproduction is simple. | Mode of reproduction is complex. |
| It involves the division of parental cells. | It involves the formation of specialised cells. |
| Mostly involves a single parent. | Involves a single or two parents. |
| Fertilization does not takes place in most of the organisms. | Fertilization process takes place. |
| Eg: Fission, budding, etc. | Eg: Vegetative propagation, sexual reproduction, etc. |
10. How does reproduction help in providing stability to populations of species?
Answer: Reproduction ensures species stability by replacing aging individuals, introducing genetic diversity through offspring, allowing natural selection to favor advantageous traits, and maintaining ecological balance within ecosystems.
These factors collectively contribute to the survival and adaptability of a species. System is crucial for ecological balance. Reproduction ensures that species continue to exist, and their interactions with other species contribute to the overall stability of ecosystems.
11. What could be the reasons for adopting contraceptive methods?
Answer:
- Family planning: To control the timing and number of children.
- Health concerns: To prevent pregnancies that may pose health risks to the mother or child.
- Economic considerations: To manage resources and provide for children’s needs.
- Career and education: To pursue personal and professional goals before starting a family.
- Population control: To address concerns related to overpopulation and resource depletion.
- Protection against STIs: Condoms, a form of contraception, also provide protection against sexually transmitted infections (STIs).
Class 10 Science Chapter 8: How do Organisms Reproduce?
Class 10 Science Chapter 8: How do Organisms Reproduce? explores the methods and significance of reproduction in living organisms. It covers asexual and sexual reproduction, DNA’s role in heredity, human development, reproductive health, and hormonal control. The chapter provides insights into the diverse strategies employed by different organisms to ensure the continuity of life.
Helpful Resources for Class 10
- NCERT Solutions for Class 10 Maths
- NCERT Solutions for Class 10 Science
- NCERT Solutions for Class 10 Social Science
- NCERT Solutions for Class 10 English
Class 10 Science Chapter 8 CBSE Notes
The reproduction of diverse creatures is explained in NCERT Solutions for Class 10 Science Chapter 8. It also explains the male and female reproductive systems, puberty-related changes in the body, and cases of asexual reproduction, in which new generations are born from a single individual. NCERT Solutions for Science Chapter 8 in Class 10 How do organisms’ function? Reproduce illustrates how some of the most significant species reproduce in various ways based on their body design. Hydra, for example, may regenerate after being broken into pieces.
How Do Organisms Reproduce? NCERT Solutions for Class 10 Science Chapter 8
The various reproduction mechanisms are explained in NCERT Solutions for Class 10 Science Chapter 8:
- Sexual reproduction
- Flowering plant reproduction
- It states that reproduction entails the synthesis of a DNA copy and other cellular devices by the cell participating in the process.
- The processes of DNA copying are described in detail.
NCERT Solutions for Class 10 Science Chapter 8: Key Features What Happens When Organisms Reproduce?
- These solutions would be useful for CBSE Term-II examinations, Science Olympiads, and other competitive exams.
- The language used in NCERT Solutions is simple enough for students to understand.
- Our subject specialists prepare these solutions after conducting a significant study on each topic in order to present students with accurate and reliable information.
- All concerns in the respective NCERT textbooks are entirely resolved in this book.
- All questions include extensive answers to assist students in their preparations.
NCERT Solutions for Class 10 Science Chapter 8 Provides Key Information
Outline the topics covered in NCERT Solutions for Class 10 Science, Chapter 8.
- The following are the topics covered in Chapter 8 of the NCERT Syllabus for Class 10 Science:
- The many ways of reproduction in flowering plants, such as sexual reproduction, asexual reproduction, and reproduction in flowering plants, are briefly outlined.
- Students can comprehend that reproduction entails the formation of extracellular devices by the cell participating in the DNA copying process.
- The mechanisms of DNA copying are briefly explained.
- This chapter discusses body design and the utilization of various reproduction modes by different creatures.
Why is it important to study the NCERT Solutions for Class 10 Science Chapter 8 for the CBSE Term II exams?
Class ten is regarded as one of the most important milestones in a student’s life. INFINITY LEARN’S professors-built chapter-by-chapter solutions for this goal after performing extensive research on each issue.
To help students succeed in the CBSE Term II exams, the solutions include extensive and step-by-step explanations. On INFINITY LEARN’S, solutions are available in PDF format, which students can download and use according to their needs.
FAQs on Class 10 Science Chapter 8 How do Organisms Reproduce
Do all organisms show growth?
Yes, virtually all organisms exhibit growth as they progress through their life cycles. This growth involves an increase in size and is essential for development and survival. From plants reaching for sunlight to animals gaining mass, growth is a fundamental characteristic of life.
Why do organisms need water?
Water is a fundamental requirement for organisms. It serves as a universal solvent, facilitating chemical reactions within cells. It aids in nutrient transport, temperature regulation, and maintaining cell turgidity in plants. Without water, life processes would be severely hindered or cease to function.
Do all living organisms need to eat?
Yes, almost all living organisms, including plants, animals, and microorganisms, require some form of sustenance. Consuming food provides energy, raw materials for growth and repair, and essential nutrients vital for various metabolic processes.
Why do organisms take food?
Organisms consume food to extract energy and essential nutrients. The energy obtained from food fuels biological activities, while nutrients like vitamins and minerals support growth, repair, and the proper functioning of cells and organs.
How do organisms reproduce which chapter?
The chapter dedicated to reproduction, typically found in biology or science textbooks, explains how various organisms reproduce. It covers both sexual and asexual reproduction methods and their significance in maintaining species continuity.
What are the 3 types of reproduction?
The three primary types of reproduction are asexual reproduction (involving a single parent), sexual reproduction (involving two parents and genetic diversity), and vegetative reproduction (common in plants, using stems or roots).
What is reproduction Class 8 short?
In Class 8, reproduction refers to the biological process through which living organisms generate offspring of the same species. This process is crucial for species survival and involves various mechanisms, such as sexual and asexual reproduction.
Why do organisms reproduce Class 8?
Organisms reproduce in Class 8 to ensure the perpetuation of their species. Reproduction allows them to pass on their genetic information to the next generation, ensuring the survival and diversity of their kind. It is a fundamental biological process essential for the continuation of life.
