RBSE Class 8 Science Chapter 6 Reproduction in Plants Textbook Solutions

RBSE Class 8 Science Chapter 6 Reproduction in Plants solutions is an important chapter for students, as this gives them an opportunity to learn about plants. We have brought the solutions of this chapter from which students can revise all the important concepts and score well in the exams. These solutions will help build a solid foundation for students to understand all the key concepts of this chapter and excel in it thoroughly. All the important topics and questions of the RBSE Class 8 Science Solutions for Chapter 6 have been extensively covered to make it easier for learners to grasp the concepts with ease.

For the convenience of students, we have given chapter-wise explanations of important questions of RBSE Class 8 Science, and we hope students can benefit from this opportunity while preparing for the RBSE Class 8 2020 exam. Here, we bring you a collection of the Important Topics and Questions for all the important chapters of RBSE Class 8 Science.

In this article, we have covered the important topics and questions with solutions for Chapter 6 from the RBSE Class 8 Science Syllabus. Students can practice from these questions and get a thorough understanding of the chapter and revise it completely before the exams. This will help them to learn various interesting topics and score high grades in the exams.

Rajasthan Board Class 8 Science Chapter 6: BYJU’S Important Questions & Answers

RBSE Class 8 Science Chapter 6 Objective Questions: Textbook Important Questions and Solutions

Multiple Choice Questions (MCQs)

Mark the correct options:

Question 1: Vegetative reproduction is found in

1. Potato
2. Wheat
3. Neem
4. Pea

Answer: a) Potato

Question 2: Fusion of male and female gametes is called

1. Pollination
2. Fertilization
3. Budding
4. Spore

Answer: b) Fertilization

Question 3: Unisexual flower is

1. Maize
2. Mustard
3. Rose
4. Petunia

Answer: a) Maize

Question 4: Bisexual flower is

1. Papaya
2. Maize
3. Cucumber
4. Mustard

Answer: d) Mustard

Fill in the blanks:

Question 5: Fern and moss reproduces by ____________________________ .

Answer: asexual reproduction

Question 6: To produce _______________ of their own kind is called ___________ .

Answer: offspring, reproduction

Question 7: ____________ is formed by the fusion of male and female gametes.

Answer: Zygote

Question 8: In _____________ pollens from the anthers reach the stigma of the same flower.

Answer: self pollination

Match the following:

Answers:

Additional Multiple Choice Questions (MCQs)

Choose the correct options for the following:

Question 13: Which part of the flower becomes a fruit after fertilization?

1. Ovules
2. Parent
3. Ovary
4. Male gamete

Answer: c) Ovary

Question 14: A potato propagates through which of the following processes?

1. Tissue culture
2. Layering
3. Vegetative reproduction
4. Grafting

Answer: c) Vegetative reproduction

Question 15: How many laws of inheritance were formulated by Gregor John Mendel?

1. 2
2. 4
3. 3
4. 6

Answer: c) 3

RBSE Class 8 Science Chapter 6 Short Answer Type Questions: Textbook Important Questions and Solutions

Question 1: Describe the various processes of asexual reproduction. Give an example of each.

Answer: Asexual reproduction takes place through the following procedures:

1. Budding: From a nearby bakery shop, get some yeast powder and add a pinch of it in a bowl containing water. Now add 1 teaspoonful of sugar and mix well. Keep the mixture in a warm place. After an hour, take a drop of this liquid on a glass slide and observe it under a microscope. You will notice that new yeast cells have come up and buds have formed in these cells as a small bulb. In due course of time, the bud grows and when it separates out from the parent, new yeast cells are formed.
2. Fragmentation: The green slippery growth that you find in ponds or stagnant water is known as algae. These algae grow speadily by fragmentation under favourable conditions and each fragment forms a new alga. For example: Spirogyra.
3. Spore formation: When we keep the pieces of bread in moisture, we would notice after sometime that cotton web like fungi have developed. It contains black brown spores. When these spores release in air as they are light in weight, they are spread upto a great distance. Each spore, due to adverse conditions like high temperature and low moisture forms a hard coating around it. Under favourable conditions, the spores germinate and form fungal filaments like Mucor and Rhizopus. Such reproduction generally occurs in lower groups of organisms like – algae, fungi, moss and fern.

Question 2: Differentiate between unisexual and bisexual flower.

Answer:

Unisexual flowers: Flowers have reproductive organs. The flowers in which either androecium (male reproductive organ) or gynoecium (female reproductive organ) are present are known as unisexual flowers. For example, maize, papaya, etc.

Bisexual flowers: Those flowers in which both androecium (male reproductive organ) or gynoecium (female reproductive organ) are present are known as bisexual flowers. For example, rose, mustard, etc.

Question 3: Differentiate between self pollination and cross pollination.

Answer: Below is the difference between self pollination and cross pollination:

Question 4: Draw a labelled diagram of a flower.

Answer: Given below is a diagram of Datura flower:

Question 5: Explain parthenocarpy with an example.

Answer: When the ovary of a plant directly develops into fruit without fertilization, this is known as parthenocarpy. Fruits develop in such a way that they do not contain any seeds. For example: grapes, banana, etc.

Question 6: Write the three laws of inheritance given by Mendel.

Answer: Mendel formulated the three laws of inheritance which are listed as below:

1. Law of Dominance

2. Law of Segregation

3. Law of Independent Assortment.

RBSE Class 8 Science Chapter 6 Long Answer Type Questions: Textbook Important Questions and Solutions

Question 7: Differentiate between sexual and asexual reproduction.

Answer: Given below is the difference between sexual and asexual reproduction:

Question 8: Explain the process of sexual reproduction with a diagram.

Answer: Sexual reproduction in Plants: In the plant kingdom, the most highly advanced plants are the flowering plants. The flower of a plant usually bears the sex organs. Some plants have both male and female sex organs in them. Such kind of plants are also known as bisexual or hermaphrodite. The flowers of plants in which either the male and female sex organ is present, those are known as unisexual plants. We can learn the sexual reproduction process of the Datura flower. The swollen apical end of the pedicel of the flower is known as thalamus. The four whorls of the flower are called calyx, corolla, androecium and gynoecium.

Androecium and gynoecium are called reproductive whorls of the Datura flower. The calyx and corolla are considered as the accessory whorls or supporting whorls. The outermost whorl which are made up of green leaf-like structures is known as the calyx and each of its members is known as sepal. There is another beautiful whorl of white leaves inside the calyx which is known as corolla. Each member is known as a petal. Both the whorls are collectively known as accessory whorls.

Stamen, which is a member of androecium, is a stalk-like structure with a flattened top, the anther or pollen sacs. In anther, the male generative cells generate pollen grains. Each pollen grain is divided to form two male gametes. The carpel, a member of gynoecium whorl, is usually the female organ which has three parts. The basal swollen part is the ovary which encloses the ovules and each ovule consists of one female gamete-egg. A long, tubular structure that is developed above the ovary is known as the style. The stigma is the top flat end of the style.

Question 9: Explain the various processes of vegetative reproduction with examples.

Answer: Given below are the various processes of vegetative reproduction:

1. Cutting: It is the vegetative reproductive process in which a portion of the plant that contains the leaf buds is cut away from the parent plant. It is then induced in order to form the roots and shoots in a favourable environment, such as by digging it into the moist soil with adequate nutrients. This proves beneficial as new plants can be obtained from a single parent in a shorter span of time. Examples include banana, sugarcane, etc.

2. Grafting: Grafting is the method of propagating plants where parts of one single plant are mixed with another plant. From one plant, its roots are selected which is called the stock. From another plant, the stems, leaves, flowers or fruits are selected and referred to as the scion. The scion obtains the essential nutrients from the stock. The resultant plant therefore, possesses the rich features of both the grafted plants. Examples of grafting include producing delicious

varieties of apples and mangoes.

3. Layering: Layering usually involves plants having long and flexible branches where one branch of the stem is still attached to the main plant. It is brought in direct contact with moist soil so that it spreads out its roots. Once the roots emerge, a new sapling is formed. Later, these plantlets can be separated from the main parent plant and grow as individual plants. Examples include raspberry, grapes, jasmine, etc.

4. Tissue culture: Plant tissues have the capability to generate a whole new set of plants. Plant tissue culture is, therefore, a collection of methods used to grow or maintain plant cells, tissues or organs of plants under sterile conditions. Once the plant is infused with essential nutrients, it is then treated with root and shoot and chemicals in the laboratory. Once it gradually develops into a plantlet, it is planted into the soil in a nursery and raised as a full-grown plant. Examples include orchids, bananas, chrysanthemums, etc.

RBSE Class 8 Science Chapter 6 Additional Questions and Solutions

Short Type Answer Questions

Question 1: Define reproduction.

Answer: Every organism, whether a plant or an animal takes birth on earth has an inevitable death. In order to maintain continuity of its species, every living organism produces its own type of offspring. This process of producing offspring of its own type is known as reproduction. This is an ongoing process and will always continue to do so from one generation to generation.

Question 2: What are the different types of reproduction in plants?

Answer: There are four types of reproduction in plants which are listed below:

1. Vegetative reproduction
2. Sexual reproduction
3. Asexual reproduction
4. Parthenogenesis

Question 3: Define vegetative reproduction.

Answer: The development process of a new plant in which it develops from any vegetative part of a plant, irrespective of the seed, is known as vegetative reproduction.

Question 4: What are the benefits of vegetative reproduction?

Answer: Given below are the benefits of vegetative reproduction:

1. Plants tend to develop in a shorter span of time.
2. Fruits and flowers are obtained in a lesser time period.
3. The new plants are acquired from a single parent.
4. In this type of reproduction, parental characters are conserved as the plants are genetically identical.

Question 5: What are clones?

Answer: Plants developed through the vegetative reproduction process are usually identical to their parent plant and are called clones. For example, grass, onion, jasmine, potato, etc.

Question 6: What is a Node?

Answer: A node is that part of the plant from where the leaves, flowers and branches start growing. Nodes are capable of holding several buds and leaves, which further grow and spread into branches. In some plants, the nodes can also produce adventitious roots too.

Question 7: What is asexual reproduction?

Answer: The process of reproduction in which a single parent is involved as there is no union of gametes and the number of chromosomes remain constant is known as asexual reproduction.

Question 8: Define fragmentation.

Answer: Fragmentation in multicellular organisms is a type of asexual reproduction in which an organism is broken down into fragments. The green slippery growth that we see in ponds or stagnant water results in algae. This algae tends to grow speedily in fragments under favourable circumstances as each fragment forms a new alga. An example of fragmentation is Spirogyra.

Question 9: What is sexual reproduction in plants?

Answer: Sexual reproduction is the union of gametes, which results in the formation of an offspring in the developed plants (angiosperm) that is genetically different from either of the parents. The endosperm is triploid in angiosperms.

Question 10: What is a calyx?

Answer: The outermost whorl which is made up of green leaf-like structures that forms part of a flower is known as a calyx.

Question 11: Define corolla.

Answer: There is a beautiful whorl of white leaves inside the calyx which is known as corolla. It is that part of a flower that consists of the separate petals and constitutes the inner whorl of the plant. The reproductive parts of a flower are present inside the corolla.

Question 12: What is Androecium?

Answer: The male reproductive organ of a flower is popularly known as the Androecium. It is the third whorl of a flower which consists of male reproductive units called stamens. Each stamen has a long stalk which is known as a filament. There is a cluster of microsporangia at the top of the filament which is called the anther.

Question 13: Define Gynoecium.

Answer: Gynoecium refers to the female reproductive organ of a flower that produces ovules and is typically surrounded by the pollen-producing ultimately units called stamens which develop into the fruit and seeds. The gynoecium has stigma, style and ovary. An ovary contains many ovules in it and the female gamete or egg are usually formed in the ovule.

Question 14: What is Pollination?

Answer: The transfer of the pollen grains from the pollen sacs to the stigma of a flower through any agent insects, animals, water or air is called pollination.

Question 15: What are the types of pollination?

Answer: There are two types of pollination, namely:

1. Self pollination
2. Cross pollination

Question 16: Define heredity.

Answer: The process by which hereditary or parental characters transfer from one generation to another through offsprings is known as heredity. For this reason, the seed of a plant or an animal gives birth to a similar type of offspring.

Question 17: How does sexual reproduction in plants take place?

Answer: Sexual reproduction usually takes place in higher classes of plants in which there is a union of male and female gametes.

Question 18: How is pollination carried out?

Answer: Pollination can be carried out by any of the agents such as air, water, animals or insects.

Question 19: Name the largest and smallest flower in the world.

Answer: The name of the largest flower is Rafflesia and the name of the smallest flower is Wolfia.

Question 20: Name the largest seed and smallest seed in the world.

Answer: The name of the largest seed is Lodoesia and the name of the smallest seed is Orchid.

Question 21: Who is known as the Father of Genetics?

Answer: Gregor John Mendel is known as the Father of Genetics through his work on pea plants. He is the one who discovered the fundamental laws of inheritance.

Question 22: What are the scars of a potato called?

Answer: The scars of a potato are known as its eyes. New roots of a potato plant grow from its eyes.

Long Type Answer Questions

Question 23: Describe Fertilization.

Answer: When the pollen grains reach the stigma of gynoecium and get germination by pollination, a pollen tube arises and reaches the ovule in the ovary through the style. The male nuclei that is present in the pollen tube fuses with the egg cell in the ovule by creating a fusion of male and female nuclei that is known as Fertilization.

Fertilization results in the diploid zygote which is further divided to form an embryo. After fertilization, the seed develops from the ovule and the fruit develops from the ovary. When the fruit is utilised, the seeds become free and germinate to form a new plant.

Question 24: What is a fruit? Explain its types.

Answer: A fruit is usually formed in a mature ovary of a flower. The walls of the ovary result in the formation of the walls of the fruit. Fruits mainly consist of two types:

1. True Fruit
2. False Fruit
3. True Fruit: Those fruits which develop from only the ovary of a plant are known as true fruits.
4. False Fruit: Sometimes the floral parts apart from the ovary like thalamus or calyx also helps in formation of fruits. These are known as false fruits. Example: Pear and apple are false fruits.

Question 25: Describe the classification of fruits.

Answer: All fruits are usually classified into 3 categories:

1. Simple fruit
2. Aggregate fruit
3. Composite fruit
4. Simple fruit: When a single fruit develops from the ovary of a flower, it is referred to as a simple fruit. Examples: wheat, mango, etc.
5. Aggregate fruit: When many fruits develop from polycarpellary and apocarpous gynoecium and remain as a group, it is known as aggregate fruit. Example: strawberry.
6. Composite fruit: In formation of a fruit, when all the flowers of an entire inflorescence participate together, that is known as composite fruit. Example: custard apple, mulberry, etc.

Question 26: Describe the list of contrasting traits of a pea plant studied by Mendel.

Answer: Mendel referred the carriers of the seven pairs of contrasting traits of a pea plant as factors. Nowadays we popularly call them genes. The list of contrasting pairs of traits are given below:

We hope that the above mentioned solutions of “RBSE Class 8 Science Chapter 6 Reproduction in Plants” will help students build a strong foundation of the different concepts mentioned in the chapter.