NCERT Solutions for Class 12 Biology Chapter 1 - Reproduction in Organism
The process of reproduction assists one to give birth to their offspring. It is a natural procedure which all living beings must follow for continuity of life on earth. Also, it can be taken as an entire life cycle of an organism, starting from birth, development and finally, death.
NCERT Solutions Biology Class 12, chapter 1 will make learners comprehend the different reproduction methods of organisms. High emphasis is given on this subjective topic such that you can have a clear understanding of the same, and also know how to write the solutions.
NCERT Class 12 Biology Chapter discusses in detail the process of reproduction in organisms. It explains the types of reproduction in living organisms, i.e., sexual and asexual reproduction. Various diagrams and illustrations are provided to help the students understand the difference between the sexual and asexual modes of reproduction.
Some of the important topics discussed in this chapter are mentioned in the table below:
Topics Covered in NCERT Class 12 Biology Chapter 1 - Reproduction in Organism
Modes of Reproduction in Organism
Pre-fertilization and post-fertilization events
Importance of Class 12 Biology Chapter 1 Topics
NCERT Solutions for Class 12 Biology Chapter 1 holds an important weightage in Class 12 Board exam. The topics covered are important to clear your concepts on different modes of reproduction in organisms. It gives a clear picture of the differences between sexual and asexual reproduction. In comparison to asexual reproduction, the sexual mode of reproduction is a more complex and slow process. The majority of higher animals reproduce nearly through the mode of sexual reproduction. Asexual reproduction is common in organisms such as fungus, algae, and some invertebrate organisms. Asexual reproduction produces identical offspring, which are referred to as clones. This chapter is also important to understand the process of mitosis, meiosis and post-fertilization events.
Reproduction in Organisms Chapter at a Glance- Class 12 NCERT Solutions
Life Phases in Organisms
Organisms may be bisexual or unisexual.
Sexuality in plants is varied, particularly in angiosperms, due to the production of diverse types of flowers. Plants are defined as monoecious and dioecious. Flowers may be bisexual or unisexual flowers.
Gametes are haploid in nature and usually a direct product of meiotic division except in haploid organisms where gametes are formed by mitosis.
Transfer of male gametes is an essential event in sexual reproduction. It is relatively easy in bisexual organisms. In unisexual animals it occurs by copulation or simultaneous release. In angiosperms, a special process called pollination ensures transfer of pollen grains which carry the pollen grains to the stigma.
Pollination is of two types: Self-pollination and Cross-pollination.
Based on the source of fusing gametes, syngamy (fertilization) is of two types: Self-fertilization (Endogamy) and Cross-fertilization (Exogamy).
In flowering plants, after fertilization, ovary develops into fruit and ovules mature into seeds. Inside the mature seed is the progenitor of the next generation, the embryo.
The development of an egg (ovum) into a complete individual without fertilization by a sperm is known as parthenogenesis. It is of two main types: Natural and artificial.
Class 12 NCERT Solutions for class 12 Biology Chapter 1- Reproduction of Organisms
1.Why is reproduction essential for organisms?
Ans: Reproduction is important for organisms due to the fact that by reproduction we will reproduce our younger ones who're much like us in a maximum of our characters. Reproduction allows us to keep the existence of species even after our death. This process also helps to create recombination by the process of meiosis. It is a source of genetic recombination.
2.Which is a better mode of reproduction sexual or asexual? Why?
Ans: Sexual reproduction is known to be a better way of reproduction found in organisms. This method is found to be better because it enables new variants to be formed by combining the DNA of two different individuals, typically one of each species. This means that it involves the fusion of gametes of both the individuals i.e male and female to produce zygotes. This variation which was developed in offspring enables them to adapt to changing and challenging environments. In addition, it leads to the development of adapted organisms that ensure greater survival of a species. Conversely, asexual reproduction allows little or no variation. As a result, the individuals who are produced are found to be exact copies of their parents and themselves.
3.Why is the offspring formed by asexual reproduction referred to as clones?
Ans: Clone is a word denoted to a group of genetically identical organisms. As we all know, that only a single parent is involved in asexual reproduction, the offspring which is produced is genetically identical to the parent cell. As we all know that they are exact copies of their parents, the offspring is said to be a clone. This type of reproduction can be seen in many prokaryotic organisms and even in a few eukaryotic single-celled and multi-celled organisms.
4. Offspring formed due to sexual reproduction have better chances of survival. Why? Is this statement always true?
Ans: Yes, offsprings that are produced via sexual reproduction tend to have better survival rates as compared to asexual reproduction. This is due to the fact that during sexual reproduction, the gametes of both of the parents, male and female, come together and fuse. Thus, the offspring carries the genetic material from both parents. This means that it involves the fusion of gametes of both the individuals i.e male and female to produce zygotes. This variation which was developed in offspring enables them to adapt to changing and challenging environments. In addition, it leads to the development of adapted organisms that ensure greater survival of a species.
5.How does the progeny formed from asexual reproduction differ from those formed by sexual reproduction?
Ans: The difference between progeny formed from asexual reproduction from those formed by sexual reproduction are as follows-
Progeny Formed From Asexual Reproduction
Progeny Formed From Sexual Reproduction
Asexual reproduction is defined as the mode of reproduction that does not involve the fusion of the male and the female gamete. Organisms that are undergoing this mode of reproduction produce offspring that are morphologically and genetically identical to them.
Sexual reproduction is defined as the mode of reproduction that involves the fusion of the male and the female gamete of two individuals, typically one of each sex. Organisms that are undergoing this mode of reproduction produces offspring that are not identical to them.
Clone is a word denoted to a group of genetically identical organisms. As we all know, only one parent is involved in asexual reproduction, the offspring produced is genetically identical to the parent cell. Since they are exact copies of their parents, offspring are said to be cloned.
During sexual reproduction, the gametes of both of the parents, male and female, come together and fuse. Thus, the offspring has the genetic material of both the parents. This variation which was developed in offspring enables them to adapt to changing and challenging environments.
6. Distinguish asexual and sexual reproduction. Why is vegetative reproduction also considered a type of asexual reproduction?
Ans: The difference between asexual reproduction and sexual reproduction are as follows-
It is Uniparental.
It is Biparental.
Gametes are not involved in this type of method.
Gametes are involved in this type of method.
The only mitotic division takes place here.
Both meiosis and mitosis will take place. Meiosis occurs during gamete production and is followed by mitosis following fertilisation.
Offspring are genetically similar to the parent
Offspring are different from parents.
It is a type of process in which new plants are obtained without the production of sexual structures i.e seeds or spores. It involves the propagation of plants through different types of vegetative parts such as the rhizome, sucker, tuber, bulb, etc. In this, a fusion of the male and the female gamete does not take place and requires only one parent. Hence, vegetative reproduction can be stated under the category of asexual reproduction.
7.What is vegetative propagation? Give two suitable examples.
Ans: Vegetative propagation is defined as an asexual mode of reproduction in which new plants are obtained from the vegetative parts of the plant. It does not include the production of seeds or spores for new plants to propagate. Vegetative parts of plants include rhizomes, tubers, runners, etc. They can be used as reproductive organs to grow new plants.
Some of the examples of vegetative propagation are:
Eyes of potato:
The surface of the potato has many buds on it called eyes. Each of these eyes, when buried in the ground, becomes a new plant that is identical to the mother plant.
Eyes of Potato
Leaf buds of Bryophyllum:
Bryophyllum plant leaves have multiple adventitious buds on their edges. These shoots have the ability to grow into tiny plants when the leaves break off the plant and come in contact with moist soil.
Leaf buds of Bryophyllum
Ans: The juvenile phase of an organism's life is described as the time of growth that begins after birth and ends before it achieves reproductive maturity. It is often termed the vegetative phase.
Ans: The reproductive phase is defined as the period when an individual organism is sexually active and attains reproductive maturity. In this phase, the production of gametes also takes place.
Ans: The senescence phase is the time after the reproductive phase when a cell loses its ability to reproduce. Here the cell can grow old and stop dividing, but it does not die. This is also known as cell ageing.
9. Higher organisms have resorted to sexual reproduction despite its complexity. Why?
Ans: Higher organisms have resorted to sexual replication even after having such complexity because offspring of sexual reproduction have variations in their genes which helps their survival. It helps organisms to adapt to the environment easily. This is due to the fact that during sexual reproduction, the gametes of both of the parents, male and female, come together and fuse. Thus, the offspring tends to have the genetic material or information carried from both parents. This means that it involves the fusion of gametes of both the individuals i.e male and female to produce zygotes. This variation which was developed in offspring enables them to adapt to changing and challenging environments.
10. Explain why meiosis and gametogenesis are always interlinked?
Ans: Meiosis is the process of cell division that reduces the number of chromosomes by half, and gametogenesis is the formation of male and female gametes. These two terms are often linked because gametes are only formed in diploid organisms through meiosis. Meiosis (reduced division) produces four gametes from a germ cell. Male and female gametes combine during fertilisation, resulting in a diploid zygote (i.e. with paired chromosomes).
11. Identify each part in a flowering plant and write whether it is haploid (n) or diploid (2n).
Ans: Ovary Diploid (2n).
Ans: Anther Diploid (2n)
Ans: Egg Haploid (n)
Ans: Pollen Haploid (n)
Ans: Male gamete Haploid (n)
Ans: Zygote Diploid (2n)
12. Define external fertilization. Mention its disadvantages.
Ans: External fertilization is defined as the process by which the fusion of the male and female gametes takes place outside the female body in an external environment, generally water. Animals that show external fertilization are fish, frogs, starfish, etc. External fertilization has certain disadvantages: external fertilization gives the eggs a lower chance of fertilization, which can result in large numbers of eggs being wasted during this process; In addition, there is a lack of adequate parental care for the offspring, resulting in a low survival rate in progress.
13. Differentiate between a zoospore and a zygote.
Ans: Difference between a zoospore and a zygote:-
Zoospore is found to be a type of spore that is motile and asexual that utilizes the flagella for movement.
A zygote is known to be a type of spore which is the non-motile diploid cell, which is formed as a result of fertilization.
Zoospore is an asexual reproductive structure.
A zygote is formed as a result of sexual reproduction.
Its ploidy may vary, haploid or diploid.
It is always diploid.
14. Differentiate between gametogenesis from embryogenesis.
Ans: Difference between gametogenesis and embryogenesis:-
Gametogenesis is defined as the process of the formation of haploid male and female gametes from diploid meiocytes through the process of meiosis.
Embryogenesis is defined as the process of the development of the embryo from the repeated mitotic divisions of the diploid zygote.
Gametes which are formed are haploid.
Embryo formed has 2n ploidy.
In this, both mitosis and meiosis occur.
In this, the only mitosis occurs.
15. Describe the post-fertilization changes in a flower.
Fertilization is the process of the fusion of the male and the female gamete, which leads to the formation of a diploid zygote.
Once fertilization takes place, the sepals, petals, and stamens of the flower wither and fall off. The pistil, however, stays connected to the plant.
The zygote then develops into the new part which is known as an embryo and the ovules change into the seed.
The ovary develops into the fruit which develops a thick wail referred to as pericarp that is shielding in function.
In the end, Ovule develops into seed and ovary into fruit.
16. What is the bisexual flower? Collect five bisexual flowers from your neighborhood and with the help of your teacher find out their common and scientific names.
Ans: A flower that contains both of the reproductive structures i.e the male and female reproductive structure (stamen and pistil) is called a bisexual flower. Examples of plants which bisexual flowers are:
Water lily - scientific name -Nymphaea odorata
Rose - scientific name -Rosa multiflora
Hibiscus - scientific name -Hibiscus rosa-sinensis
Mustard - scientific name -Brassica nigra
17. Examine a few flowers of any cucurbit plant and try to identify the staminate and pistillate flowers. Do you know any other plant that bears unisexual flowers?
Cucurbit Plant Flower
The cucurbits have unisexual flowers. These types of flowers have stamen or pistil. Staminate flowers, for example, feature vivid yellow petals and stamens, which indicate the male reproductive mechanism. On the other hand, Pistilized flowers only have the pistil, which represents the female reproductive structure. If the fruit is visible in a fertilized female flower, it is very small and hardly visible. Other examples of plants that have unisexual flowers are papaya, corn, cucumber, etc.
18.Why are offspring of oviparous animals at a greater risk as compared to offspring of viviparous animals?
Ans: Egg-laying animals which are commonly called oviparous lay eggs outside their bodies. Due to this reason, the eggs of these animals are constantly threatened by various environmental factors. On the other hand in viviparous animals, the development of the egg takes place within the body of the female. protects the embryo or fetus from predators. Therefore, the offspring of an egg-laying or egg-laying animal are at greater risk than the offspring of a viviparous animal that gives birth to its young.
Reproduction in Organisms Class 12 NCERT PDF
The solutions of Biology Class 12, chapter 1 are prepared in a free PDF format. By downloading and studying from these solutions, you will be able to clear doubts and have the confidence to tackle the 12th board exam.
NCERT Solutions for Class 12 Biology Chapter 1 Reproduction in Organisms
This Biology NCERT solution contains 18 key questions from the chapter Reproduction in Organisms, and here is a brief discussion. Take a look!
Reproduction in Organism’s Class 12 NCERT Solutions: Question 1
In the first question, students need to discuss how essential reproduction is to continue an organism’s generation. You can also put more light on the three different life phases. Without reproduction, there will be no existence of life on the planet.
Reproduction in Organism’s Class 12 NCERT Solutions: Question 2
In the second question, you will have to write the comparison between sexual and asexual reproduction, and state which mode is better by providing relevant justification.
Reproduction in Organism's Class 12 NCERT Solutions: Question 3
This question asks students the reason why offspring produced from asexual reproduction is referred to as a clone.
Reproduction in Organism's Class 12 NCERT Solutions: Question 4
In this question, you need to write about why sexual reproduction is considered a better mode of reproduction. The child produced by sexual reproduction has maximum chances of survival.
Reproduction in Organism's Class 12 NCERT Solutions: Question 5
Biology Class 12 chapter 1 question 5 is about the difference between progeny formed asexual and sexual reproduction.
Reproduction in Organism's Class 12 NCERT Solutions: Question 6
This question asks students to distinguish between asexual and sexual reproduction, and why vegetative reproduction falls under the category of asexual reproduction.
Reproduction in Organism's Class 12 NCERT Solutions: Question 7
In this question, you will have to write about vegetative propagation and support your answer with examples like:
Diagram showing the eyes of a potato
(Image will be uploaded soon)
Reproduction in Organism's Class 12 NCERT Solutions: Question 8
This question is about defining juvenile phase, reproduction phase and senescent phase.
Reproduction in Organism's Class 12 NCERT Solutions: Question 9
Question 9 asks students to write why higher organisms use the sexual reproduction method, though being complex.
Reproduction in Organism's Class 12 NCERT Solutions: Question 10
This question requires an explanation about the link between meiosis and gametogenesis.
Reproduction in Organism's Class 12 NCERT Solutions: Question 11
In this question, students will have to identify the parts of flowering plants and mention whether they are diploid or haploid.
Reproduction in Organism's Class 12 NCERT Solutions: Question 12
Biology Class 12 chapter 1 question 12 requires the definition of external fertilisation and the disadvantages of the same.
Reproduction in Organism's Class 12 NCERT Solutions: Question 13 and 14
These two questions ask the differences between zygote and zoospore, and gametogenesis and embryogenesis, respectively.
Reproduction in Organism's Class 12 NCERT Solutions: Question 15
Here, students will have to describe the changes that take place during post-fertilisation in flower.
Reproduction in Organism's Class 12 NCERT Solutions: Question 16
This question is about the explanation of bisexual flowers, and asks the learners to collect five bisexual flowers from their surrounding areas, and seek for their scientific and common names.
Reproduction in Organism's Class 12 NCERT Solutions: Question 17
Question 17 asks the students to inspect flowers of a cucurbit plant and rule out the pistillate and staminate flowers.
Reproduction in Organism's Class 12 NCERT Solutions: Question 18
In the final question, you will have to write why the offspring of viviparous animals have less risk than the offspring of oviparous animals.
Biology Class 12 Chapter 1: Marks Weightage
Reproduction in organisms is the first chapter of Unit 1 from CBSE Biology book. A total of 12 marks is set for this unit in 12th board exams, but segregation of marks for each chapter is not defined.
NCERT Class 12 Biology Other Chapter Solutions - Free PDF Download
Features of NCERT Solutions Class 12 Biology Chapter 1 - Reproduction in Organisms
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Class 12 Biology Chapter 1 NCERT Solutions Benefit
Take a look at some of the benefits of the NCERT solution of Class 12 Biology chapter 1 in preparation of board exams:
Use of simple language, such that everyone can easily comprehend them.
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Emphasis on complex topics and concepts.
Hence, it is always profitable to make use of the NCERT solutions to refrain from struggling with the questions in board exams. Download the NCERT solutions of Class 12 Biology chapter 1 PDF offered by Vedantu today!
FAQs on NCERT Solutions for Class 12 Biology Chapter 1 - Reproduction In Organism
1. What will a Student get to Learn in the Chapter of Reproduction in Organism?
This chapter of CBSE 12 comprises the topics of asexual reproduction, reproduction necessity, budding, binary fusion, fragmentation, sexual reproduction, vegetation propagation, sexual reproduction in plants and advantages of sexual and asexual reproduction.
By studying this chapter, students will get to know the processes of reproduction in detail. Moreover, this unit focuses on female and male reproductive systems, plant reproduction, contraceptive methods and fertilisation. Reproduction is essential for the progression of species on the planet. If organisms stop reproducing, there will be a discontinuity of life.
2. How is DNA Important in Reproduction? Is it Related to Proteins?
DNA is exceptionally vital for all living creatures on earth, even in plants. They are essential for coding for proteins, inheritance and acts as a guide of genetic instruction for life and related processes. DNA stores the information for each cell’s or a living being’s development, reproduction and finally death.
DNA holds the codes for proteins, but the real protein is different from the codes available on DNA. The fundamental steps included are transcription, translation, and at last, modification and folding.
3. Why is an Offspring Born from Sexual Reproduction Likely to Survive More Than Asexual Reproduction?
The mode of sexual reproduction necessitates female and male gamete fusion. During the zygote formation process, exchange of traits and genes takes place between the gametes. Similarly, during the process of chromosome segregation and crossing over, chances of elimination of non-identical characteristics are much higher. Therefore, the offspring born does not resemble its parents and hence more chances of survival. However, if the mother parent is suffering from an acute disease like AIDS, etc., the child may not survive for long.
4. What is the advantage of Vedantu’s NCERT Solutions?
Our experts have framed the solutions from the examination point of view and they are very easy for you to learn. They have explained these solutions with supporting diagrams and examples in a simple language so that you can remember them for a longer time and our well-structured explanation will help you in scoring more marks.
We have drafted these solutions in a simple and understandable language. You can learn the solutions at any time and anywhere to improve your score in the examination. Our highly experienced teaching professionals are great in providing solutions and explanations for biology Class 12 reproduction in organisms chapter.
5. Define clones according to Chapter 1 of Class 12 Biology?
During an asexual reproduction there is only one parent involved and no fusion takes place between the male and the female gamete. The offspring produced by this kind of reproduction are identical genetically and also morphologically to the parent. The offspring that do not show any variations and are vulnerable to the environment are called clones. The chapter is well defined systematically in Vedantu which becomes easy for the students.
6. What are the chapters in Biology Class 12?
There are a total of 16 chapters in Biology Class 12.
The Reproduction in Organisms.
Sexual Reproduction in Flowering Plants.
Principles of Inheritance and Variations.
Molecular Basis of Inheritance.
Human Health and Diseases.
Strategies for Enhancement of Food Production.
Microbes in Human Welfare.
Biotechnology Principles and Processes.
Biotechnology and its Application.
Organism and Populations.
Biodiversity and conservation.
7. List out the important concepts discussed in NCERT Solutions for Chapter 1 of Class 12 Biology.
The important concepts discussed in NCERT Solutions Class 12 Biology are Reproduction, Sexual Reproduction In Flowering Plants, Male And Female Reproductive Systems, Reproductive Health, Mendel’s Laws Of Inheritance, Genetics And Evolution, Common Diseases In Humans, Role Of Animal Husbandry, Microbes, Biotechnology, Biotechnological Applications In Agriculture, Hibernation, Nutrient Cycle, Biodiversity And Conservation, Air Pollution And Its Control, Water Pollution And Its Control.
8. What is Reproduction according to Chapter 1 of Class 12 Biology?
Reproduction is the process of living organisms giving birth to their young ones similar to them. This is a continuing process from one generation to another. If there is no reproduction, then the species will not live for a long time or may even become extinct. The world would have ended without this process.
9. Is Vedantu providing answers for NCERT Solutions for Chapter 1 of Class 12 Biology?
Yes, Vedantu provides the answer for NCERT Solutions for Chapter 1 of Class 12 Biology. You can download it using the link NCERT Solutions for Chapter 1 of Class 12 Biology and start preparing for the exams. The solutions provided are easy to understand. The answers are explained well, and one can rely on them for their preparation. The curriculum is updated, and there is no confusion. The sample papers and the important questions help the students in thorough preparation. These solutions are available free of cost on Vedantu (vedantu.com). You can download these using the Vedantu app as well.