Haryana State Board HBSE 8th Class Science Solutions Chapter 9 Reproduction in Animals Textbook Exercise Questions and Answers.
Haryana Board 8th Class Science Solutions Chapter 9 Reproduction in Animals
HBSE 8th Class Science Reproduction in Animals Textbook Questions and Answers
Question 1.
Explain the importance of reproduction in organisms.
Answer:
Reproduction is very important for the organisms. The organisms reproduce to produce young ones like them. It carries on their generation. If reproduction does not take place, no living being would survive on earth. Secondly, specials characters of an organism are carried over to its next generation through reproduction only.
Question 2.
Describe the process of fertilization in human beings,
Answer:
Human beings reproduce sexually. In human beings fertilization takes place internally i.e. inside female body. Males eject sperms inside females body. Sperms and ovum fuse to form the fertilized egg called zygote. During this process the nucleus of the sperm fuses with the nucleus of the ovum thus forming a single nucleus.
Thus zygote is formed with a single nucleus, this completes the process of fertilization.
Question 3.
Choose the most appropriate answer:
(a) Internal fertilisation occurs:
(i) in female body
(ii) outside female body.
(iii) in male body.
(iv) outside male body.
Answer:
(a) In female body
(b) A tadpole develops into an adult frog by the process of:
(i) fertilization
(ii) metamorphosis.
(iii) embedding
(iv) budding.
Answer:
(b) metamorphosis
(c) The number of nuclei present in a zygote is:
(i) none
(ii) one
(iii) two
(iv) four
Answer:
(c)two.
Question 4.
Indicate whether the following sentences as True (T) or False (F):
(a) Oviparous animals give birth to young ones. ( )
(b) Each sperm is a single cell. ( )
(c) External fertilisation take place in frog. ( )
(d) A new human individual developed from a cell called gamete. ( )
(e) Egg laid after fertilisation is made up of a single cell. ( )
(f) Amoeba reproduces by budding. ( )
(g) Fertilisation is necessary even in asexual reproduction. ( )
(h) Binary fission is a method of asexual reproduction. ( )
(i) A zygote is formed as a result of fertilisation. ( )
(j) An embryo is made up of a single cell.( )
Answer:
(a) False
(b) True
(c) True
(d) False
(e) True
(f) False
(g) False
(h) True
(i) True
(j) False.
Question 5.
Give two differences between a zygote and a foetus?
Answer:
(i) Zygote is made up of a single cell while foetus is made up of many cells.
(ii) Zygote does not have well developed limbs, foetus has well developed and identifiable limbs.
(iii) Zygote is formed by the fertilization of sperms and ovum, foetus is formed by the repeated divisions of the zygote .
Question 6.
Define asexual reproduction. Describe the two methods of asexual reproduction in animals.
Answer:
Asexual reproduction is that type of reproduction in which only single parent is involved. Asexual reproduction takes place by different methods like budding, binary fission etc. Let us discuss these two methods:
(i) Budding:
This type of reproduction takes place in Hydra and Bacteria. A part of the organism starts bulging out. Slowly it grows and develops into a separate individual.
(ii) Binary fission:
In this type of reproduction, a single organism gets divided into two. This type of reproduction takes place in Amoeba. The nucleus of the Amoeba gets divided into two followed by division of their bodies, each part getting one nucleus and developing into separate individual.
Question 7.
In which female reproductive organ does the embryo get embedded?
Answer:
Uterus.
Question 8.
What is metamorphosis? Give examples.
Answer:
Drastic changes which take place during the development of an animal is called metamorphosis. Animals like frog, butterfly undergo metamorphosis.
Question 9.
Differentiate between internal fertilisation and external fertilisation.
Answer:
Internal fertilisation takes place inside the body of the female while the external fertilisation takes place outside the body of the female.
In case of internal fertilisation sperms are ejaculated in female’s body by the male. In external fertilisation sperms are discharged in I open.
Question 10.
Complete the cross-word puzzle using the hints given below.
Across:
1. The process of the fusion of the gametes.
6. The type of fertilization in hen.
7. The term used for bulges observed on the sides of the body of Hydra.
8. Eggs are produced here.
Down:
2. Sperms are produced in these male reproductive organs.
3. Another term for the fertilized egg.
4. These animals lay eggs.
5. A type of fission in amobea.
Answer:
Extended Learning – Activities And Projects
1. Visit a poultry farm. Talk to the manager of the farm and try to find out the answers to the following:
(a) What are layers and broilers in a poultry farm?
(b) Do hens lay unfertilised eggs?
(c) How can you obtain fertilised and unfertilised eggs?
(d) Are the eggs that we get in the stores fertilised or unfertilised?
(e) Can you consume fertilised eggs?
(f) Is there any difference in the nutritional value of the fertilised and unfertilised eggs?
Answer:
For self attempt.
2. Observe live hydra yourself and learn how they reproduce by doing the following activity:
During the summer months collect water weeds from ponds or ditches along with the pond water and put them in a glass jar. After a day or so you may see several hydra clinging to the sides of the jar.
Hydra is transparent, jelly-like and with tentacles. It clings to the jar with the base of its body. If the jar is shaken, the hydra will contract instantly into a small blob, at the same time drawing its tentacles in.
Now take out few hydras from the jar and put them on a watch glass. Using a hand lens or a binocular or dissection microscope, observe the changes that are taking place in their body. Note down your observations.
Answer:
For self attempts.
3. The eggs we get from the market are generally the unfertilized ones. In case you wish to observe a developing chick embryo, get a fertilized egg from the poultry or hatchery which has been incubated for 36 hours or more. You may then be.able to see a white disc-like structure on the yolk. This is the developing embryo. Sometimes if the heart and blood vessels have developed you may even see a red spot.
Answer:
For self attempt.
4. Talk to a doctor. Find out how twinning: occurs. Look for any twins in your neighbourhood, or among your Mends. Find out ifthe twins are identical or non-identical. Also find out why identical twins are always of the same sex? If you know of any story about twins, write it in your own words.
You could visit the following website for information on twins: www.keepkidshealthy.com/twins/ expecting_twins.html.
For more information , on animal reproduction, you can vjsit:
- www.Saburchill.com/chapters/ chap0031.html
- healthhowstuffworks.com/human- reproduction.htm
- www.teenshealth.org/teen/sexual_health
Answer:
For self attempt.
HBSE 8th Class Science Reproduction in Animals Important Questions and Answers
Very Short Answer Type Questions
Question 1.
Name different modes of reproduction.
Answer:
Sexual reproduction and asexual reproduction.
Question 2.
Define sexual reproduction.
Answer:
When male and female organisms are involved in reproduction, it is called sexual reproduction.
Question 3.
Define asexual reproduction.
Answer:
When only single parent involved, reproduction is called asexual reproduction.
Question 4.
What is another name for ovum or sperm?
Answer:
Gametfe.
Question 5.
What is fertilization?
Answer:
When male and female gametes fuse, it is called fertilization.
Question 6.
What is formed when male and female gametes fuse?
Answer:
Zygote.
Question 7.
Name female reproductory organs.
Answer:
Ovaries, oviduct, uterus.
Question 8.
Name male reproductory organs.
Answer:
Testes, sperm ducts and penis.
Question 9.
Name the female gamete produced by ovaries.
Answer:
Ova.
Question 10.
Which male organ produce male gamete?
Answer:
Testes.
Question 11.
Name male gamete produced by testes.
Answer:
Sperms.
Question 12.
Name the hind of fertilization *hich take, pUce inside fem.le. body.
Answer:
Internal fertilization.
Question 13.
What kind of fertilization takes place in humans?
Answer:
Internal fertilization.
Question 14.
What type of fertilization takes place in frogs?
Answer:
External fertilization.
Question 15.
What does a zygote develop into?
Answer:
Embryo.
Question 16.
Where does an embryo grow in case of internal fertilization?
Answer:
In uterus.
Question 17.
What does an embryo grow into?
Answer:
Foetus.
Question 18.
Where does an embryo grow in case of external fertilization?
Answer:
Out side in open.
Question 19.
What are the animals called, who give birth directly to young one?
Answer:
Viviparous animals.
Question 20.
Give at least two examples of viviparous animals.
Answer:
Humans and cows.
Question 21.
What are the animals called, who lay eggs first?
Answer:
Oviparous animals.
Question 22.
Give any two examples of oviparous animals.
Answer:
Hen, Frog.
Question 23.
How many developing stages an egg of a frag undergoes to become an adult?
Answer:
Three: Egg, Tadpole, larvae, adult.
Question 24.
What do we call the sudden and extreme changes taking place during the development of an animal?
Answer:
Metamorphosis.
Question 25.
Name any two methods of asexual reproduction.
Answer:
Budding and Binary fission.
Question 26.
Name any animal undergoing budding for reproduction.
Answer:
Hydra.
Question 27.
Name tuny animal undergoing Binary fission to reproduce,
Answer:
Amoeba.
Short Answer Type Questions
Question 1.
What is reproduction? Why is it important?
Answer:
Reproduction is giving birth to organisms of same kind. Reproduction is important to continue life on earth and to maintain different special characters of different species.
Question 2.
What are different modes of reproduction?
Answer:
Reproduction takes place by two methods. In one method a single parent is involved in the process of reproduction. This is called asexual reproduction. In second method both male and female i.e. both parents are involved in the process of reproduction. This kind of reproduction is called sexual reproduction.
Question 3.
What are the names of male reproductory organs in human beings?
Answer:
In human beings male reproductory organs are a pair of testes, sperm ducts and a penis. Testes are responsible for producing male gametes called sperms. They are transported to the sperm ducts and through the penis, they are ejaculated in female body.
Question 4.
Explain the reproductory organs of female in human beings.
Answer:
In human beings the female reproductoiy organs are a pair of ovaries, oviducts or fallopian tubes and the uterus. Ovaries are responsible to produce female gamete called ova, which fertilize with male sperm in female fallopian tube and travels to uterus for its development into embryo and the foetus.
Question 5.
Describe the human male and female gametes.
Answer:
In human beings the males produce the gamete called sperms. Sperms are very small in size. They have a head with a middle piece which end into a tail. It is a single cell. Similarly, female gamete ova is produced by ovaries. Every ova is a single cell and one matured ova is released by one ovary every month.
Question 6.
What is fertilisation?
Answer:
When a male and a female gamete come in contact with each other they fuse. The male sperm enters the female ova and the nucleus of the sperm fuses with nucleus of the ova and results into a single nucleus. This whole process is called fertilization. In short fertilisation is the fusion of male and female gametes.
Question 7.
Explain how external fertilization takes place?
Answer:
In this case the females lay eggs in slow moving streams. The males also release sperms on this cluster of eggs. The sperms move in water with the help of tail and when come in contact with egg, they get fertilized.
Question 8.
How is an embryo formed put of a zygote?
Answer:
Zygote is a single cell formed by the fusion of male and female gametes. It undergoes repeated numbers of division to form a lot of many cells, so that the limbs and other parts can be developed. Thus a single zygote gets divided to form an embryo.
Question 9.
How is an embryo formed in case of hens?
Answer:
In hens zygote divides many times and reaches the oviduct. During this a protective outer coating is formed around the embryo. The complete embryo develops inside this protective shell. This embryo is laid by the hen along with the shell as an egg. This egg finally hatches after ‘ three weeks to produce chick.
Question 10.
What is budding?
Answer:
Budding is an asexual method of reproduction in animals. It needs only a single parent to reproduce. The body of the animal starts developing a small bulging structure called bud which slowly grows and have itself disconnected from the parent animal and becomes a separate individual. This is called budding. Animals like hydra reproduce through budding.
Question 11.
What do you mean by binary fission?
Answer:
Binary fission is a method of asexual reproduction. In this method the body of the animal divides into two halves. The nucleus of the body divides into two and this is followed by the division of the whole body. So, two organisms get produced with separate nuclei. Animals like Amoeba reproduce by this method.
Question 12.
What is cloning?
Answer:
Cloning is a method of producing an identical organism, a body part or only a cell. The produced organism or cell is completely identical to its original organism or cell. This method has been used many times in animals to produce identical clones.
Long Answer Type Questions
Question 1.
What do you mean by reproduction? Write about different modes of reproduction.
Answer:
Reproduction is the process of producing young ones of the same kind. Reproduction is a very important process. It is the only means of keeping the life on the earth.
There are two modes of reproduction:
(i) Sexual Reproduction:
Reproduction process in which a male and a female parents are involved is called sexual reproduction. In this process both parents produce gametes which fertilize to produce a zygote, which further develops into a baby. Human beings, cows, dogs etc. reproduce sexually.
(ii) Asexual Reproduction:
When a single parent is responsible for producing a young one, it is called asexual reproduction. Budding, fragmentation, spore formation Binary fission etc. are different methods of asexual reproduction. Microorganisms like Hydra, Amoeba, bacteria etc. reproduce asexually.
Question 2.
Draw and describe the male reproductive organs in humans.
Answer:
Male reproductive organs consist of a pair of testes, sperm ducts and penis. Testes are responsible for producing male gamete called sperm. Sperm is very small in size. It has a head, a middle piece and a tail. Sperms travel through sperm ducts and penis, and are released in female body for fertilization.
Question 3.
Draw and explain the Female Reproductive organs in human.
Answer:
Female reproductive organs consist of a pair of ovaries, oviduct or fallopian tubes and uterus.
Ovaries produce the female gamete called Ova. Every month an ovary produces an ovum. The ovum and sperm fertilize inside fallopian tubes and the fertilized zygote travels to the uterus and attach with its wall to develop into the foetus.
Question 4.
What is fertilization? How does it take place?
Answer:
Fertilization is the process by which the male and female gametes fuse to form the zygote. The sperms from a male are transferred into the female body. They swim to the fallopian tubes with help of their tails and one of them enters the ovum to fertilize. When the sperm enters the ovum, the nucleus of both the gametes fuse with each other to form the fertilized zygote.
The fertilized egg is called zygote. This zygote develops into foetus by repeated cell division. When the fertilization takes in the body of female, it is called internal fertilization. But many animals release their gametes into water and fertilization takes place outside the body of female, then the fertilization is called the external fertilization.
Question 5.
What is asexusal reproduction? Describe different methods of asexual reproduction.
Answer:
The reproduction in which only a single parent is involved is called asexual reproduction. This type of reproduction takes place mostly in microoganisms. Following are the methods of asexual reproduction:
(i) Budding:
This type of reproduction takes place in Hydra. The body of the hydra starts developing small bulges. These bulges are called buds. These buds grow in size and finally get detached from its body and become a separate individual.
(ii) Binary Fission:
This type of reproduction takes place in Amoeba. The body of the organism divides into two. The nucleus of the organism divides into two and then the body of Amoeba divides, each part getting each nucleus and thus becoming two separate individuals.
Reproduction in Animals Class 8 HBSE Notes
1. Each living being reproduce to give birth to young ones exactly like them.
2. The process by which young ones are produced is called reproduction.
3. Reproduction is of two types: Sexual reproduction and asexual reproduction.
4. When a male and a female gamete fuse to give birth to a young ones, then it is called sexual reproduction.
5. When a single parent is involved in reproduction, then it is called asexual reproduction.
6. Reproductive organs in males and females are different. In females the reproductive organs are ovaries oviducts and uterus. In males the reproductive organs are a pair of testes, sperm ducts and penis.
7. Ovaries produce female gamete called ovum and male gamete called sperms are produced by testes.
8. Ovum and sperm fuse to form egg called Zygote. The process of fusion of ovum and sperm is called fertilization.
9. Fertilization is of two types: When it takes place inside the females body, then it is called internal fertilization, but when ovum and sperms fuse out side the body, it is called external fertilization.
10. Embryo is formed from the zygote by repeated divisions, which grows in the uterus of the female in case of internal fertilization. Embryo grows into foetus when it gets well developed limbs.
11. When animals give birth to a young one it is called a viviparous animals e.g. man, cow etc. When animals lay eggs, they are called oviparous animals e.g. hen, butterfly, etc.
12. In asexual reproduction organisms reproduce by budding binary fission, fragmentation etc.