Reproduction and Its Importance:
It is a process by which the organisms produce new offspring of their own species. Reproduction is important for the existence of a species.
Modes of Reproduction:
The modes of reproduction are based on the requirements of the number of parents, which are:
(1) Sexual Reproduction
(2) Asexual Reproduction
1. Sexual Reproduction
In sexual reproduction, the species consist of male and female reproductive organs. The kind of reproduction in which the fusion of male andfemale gametes takes place is called sexual reproduction.
Organs for Reproduction:
The female reproductive organs include ovaries, oviducts, and uterus whereas the reproductive organs in the male include testes, sperm ducts, and penis. The ovary produces female gametes called ova (egg cells) and the testes produce male gametes called sperms.
The fusion of these gametes (ovum and sperm) is called fertilization. The egg developed after fertilization is called a zygote.
Types of Fertilization:
The fertilization can occur inside or outside the parent body, so it is divided into two types:
(a) Internal Fertilization:
The fertilization taking place inside the body of female species is called internal fertilization. This phenomenon is observed in human beings and other animals, for example, hens, cats, dogs, and other mammals.
(b) External Fertilization:
The fertilization taking place outside the body of the female species is called external fertilization. This is generally observed in aquatic animals such as frogs, fish, etc.
Process of Fertilization:
After fertilization, a zygote is formed, which begins to develop into an embryo. The zygote divides itself repeatedly which results in an embryo, which then gets embedded in the wall of the uterus and develops into body parts. The stage when the embryo develops well-defined body parts is called the foetus.
Organisms such as humans, cats, cows, and other mammals which give birth to young ones are called viviparous animals.
Egg-laying animals are called oviparous animals, e.g., frogs, lizards, butterflies, etc.
In metamorphosis, the larva is transformed into an adult.It is not observed in humans but it is observed in insects like butterflies, silkworms, frogs, etc.
2. Asexual Reproduction
This is the type of reproduction in which only a single parent is required. Such a type of reproduction is called asexual reproduction. Species like hydra, amoeba, and other microscopic unicellular organisms.
In hydra, new individuals develop from buds formed from the parent body. This method of asexual reproduction by forming buds is called budding.
(b) Binary Fission:
When an organism reproduces by dividing itself into two from a single parent, this type of asexual reproduction is called binary fission. For example, microscopic organisms like amoeba reproduce by dividing themselves into two. In this method the organism divides its nucleus into two parts, thus each part contains a nucleus.
Revision Notes for Class 8 Chapter 9 - Download PDF
Reproduction in animals class 8 notes have been curated by experts in the subject who have carefully included all important concepts in a point format in these notes. Not only are these notes easy to read and understand, but the language used is also simple and can be retained by the students. Students can breeze through these notes and memorize all the terms and examples that have been used in the chapter. Class 8 Science Chapter 9 notes work as a useful aid at the time of the exams when students need a summary of the chapter to help them recollect the information provided in the chapter. These notes can be downloaded in PDFS from the official Vedantu’s website.
Reproduction in Animals Chapter 9 Science Notes (CBSE Class 8) - Benefits of Class 8 Chapter 9 Revision Notes
Let us check the benefits of Reproduction in Animals Chapter 9 Science Notes:
The aim of Class 8 Science Reproduction in Animals notes is to help the students in covering the entire chapter without missing out on any important concept that can come in the exams.
Most of the time, a chapter in the textbook contains exhaustive information about all the topics. This is done so that the students can understand it well but students need to write only the required portion of this material in the exams.
Science Class 8 Chapter 9 notes will help the students in revising the entire syllabus and acing their exams. The notes have been prepared in a manner that will also help the students in framing their answers.
With the help of the revision notes, students can now focus on their studies without wasting their time making the notes.
Students can understand well the whole chapter in brief from these revision notes.
Revising from these notes will help the students to stay updated with the chapter and the concepts of this chapter will remain fresh in their minds in a capsulated manner.
Reproduction in Animals Class 8 Notes CBSE Science Chapter 9 - Summar of the Notes
Reproduction in Animals is an important chapter and students need to understand its basics well as this knowledge is used as the groundwork for studies in higher classes and when students specialize in the subject of Biology.
Reproduction is the process by which organisms produce young ones of their kind. It can be classified into asexual and sexual reproduction. When reproduction results from the fusion of male and female gametes it is called sexual reproduction and when only a single parent is involved, the reproduction process is asexual. Asexual reproduction can further be classified into budding where offspring develop from buds and binary fission where amoeba reproduces by dividing itself into two. Notes on Reproduction in Animals Class 8 will help the students revise these key concepts easily before the exams.
With the help of these notes, students can easily recollect topics like the reproductive organs in the female and males. The female organs include ovaries, oviducts, and uterus while the male organs include the testes, sperm ducts, and penis.
Notes of Reproduction in Animals Class 8 can be referred to for a quick revision of concepts like fertilization which is an important part of reproduction. The process of the fusion of the ovum with the sperm is called fertilization. The fertilization process that takes place inside the body is called internal fertilization and the fertilization occurring outside the body is termed external fertilization.
The process of fertilization has been explained in simple-to-learn points in Chapter 9 Science Class 8 notes. Animals can be classified into viviparous and oviparous animals based on the offspring they produce. Animals that give birth to young ones are termed viviparous and those that lay eggs are called oviparous animals.
An advantage of these notes is that students can access the pdf file from anywhere and at any time. Going through these notes takes far less amount of time than reading the entire chapter and time is of great value during the exams.
Reproduction in Animals Class 8 CBSE Science Chapter 9- Topics Covered
Following are the topics that are covered in this chapter:
Modes of Reproduction
Male Reproductive Organs
Female Reproductive Organs
Development of Embryo
Viviparous and Oviparous Animals
Young Ones to Adults
Reproduction in Animals Class 8 CBSE Science Chapter 9- Extra Questions to Practice (Solved)
1. What do you mean by Reproduction?
Ans. Reproduction is a biological process in which new organisms are produced from their parents.
2. What do you mean by fertilization?
Ans. The fusion of ova and sperm is called fertilization.
3. What is the name of the fertilized egg?
How to Study Science in Class 8 CBSE ? - Tips to Study Better
Following are some tips to study science in a better way:
Follow the concepts well and understand the core of the chapter.
Write the concepts in your own words and see if you have understood the topic.
A chapter like reproduction consists of many biological terms which must be paid attention to.
You can draw the diagram and practice writing the notes and labeling it.
Revise the chapters regularly so that the concepts are fresh in your mind.
Hope the students have gained adequate revision material from this content. Studying from our revision notes will simplify the chapter making it capsuled for the students to prepare it before the exam. Other than this, you must pay attention to the topics covered in this chapter and also the suggestion was given by us on how to study the subject better.
Download the free pdf and enjoy free learning.