Class 10  >  Science Class 10  >  Modes of Reproduction

Modes of Reproduction - Science Class 10

Reproduction Definition

Reproduction is a life process which enables an organism to reproduce its own offspring. Thus, they continue their species without extinction.

Types of Reproduction

Reproduction can take place by the participation of a single parent or two parents. Based on this, reproduction can be classified into two types.

  • Asexual reproduction: A type of reproduction where a single parent is divided by itself and reproduce its offspring.
  • Sexual reproduction: A process where two parents participate in producing their offspring.

Asexual Reproduction

“Asexual reproduction is the mode of reproduction that is involved in the production of off springs by a single parent.”

What is Asexual Reproduction?

Asexual reproduction is a mode of reproduction in which a new offspring is produced by a single parent. The new individuals produced are genetically and physically identical to each other, i.e., they are the clones of their parent.
Asexual reproduction is observed in both multicellular and unicellular organisms. This process does not involve any kind of gamete fusion and there won’t be any change in the number of chromosomes either. It will inherit the same genes as the parent, except for some cases where there is a chance of rare mutation to occur.

Characteristics of Asexual Reproduction

Following are the important features of asexual reproduction:

  1. Single parent involved.
  2. No fertilization or gamete formation takes place.
  3. This process of reproduction occurs in a very short time.
  4. The organisms multiply and grow rapidly.
  5. The offspring is genetically similar.

Types of Asexual Reproduction

There are different types of asexual reproduction:

  • Binary Fission
  • Budding
  • Fragmentation
  • Vegetative Propagation
  • Sporogenesis

Binary Fission

The term “fission” means “to divide”. During binary fission, the parent cell divides into two cells. The cell division patterns vary in different organisms, i.e., some are directional while others are non-directional. Amoeba and euglena exhibit binary fission.
It is one of the simplest and uncomplicated methods of asexual reproduction. The parent cell divides into two, each daughter cell carrying a nucleus of its own that is genetically identical to the parent. The cytoplasm also divides leading to two equal-sized daughter cells. The process repeats itself and the daughter cells grow and further divide.

Fragmentation

Fragmentation is another mode of asexual reproduction exhibited by organisms such as spirogyra, planaria etc. The parent body divides into several fragments and each fragment develops into a new organism.
Modes of Reproduction | Science Class 10

Regeneration

Regeneration is the power of growing a new organism from the lost body part. For eg., when a lizard loses its tail, a new tail grows. This is because the specialized cells present in the organism can differentiate and grow into a new individual. Organisms like hydra and planaria exhibit regeneration.
Modes of Reproduction | Science Class 10

Budding
Budding is the process of producing an individual through the buds that develop on the parent body. Hydra is an organism that reproduces by budding. The bud derives nutrition and shelter from the parent organism and detaches once it is fully grown.
Modes of Reproduction | Science Class 10

Vegetative Propagation

Asexual reproduction in plants occurs through their vegetative parts such as leaves, roots, stem, and buds. This is called vegetative propagation. For example, potato tubers, runners/stolon, onion bulbs, etc., all reproduce through vegetative propagation.

Spore Formation

Spore formation is another means of asexual reproduction. During unfavourable conditions, the organism develops sac-like structures called sporangium that contain spores. When the conditions are favourable, the sporangium burst opens and spores are released that germinate to give rise to new organisms.
Modes of Reproduction | Science Class 10

In asexual reproduction, a single cell is divided to produce offspring. The simple cell-by-cell division is not possible in multicellular organisms. Most of the multicellular organisms have a complex body design. They have a higher level of organization like tissues, organs and organ system. Thus, they need a special mode for reproduction.

Advantages of Asexual Reproduction

Following are the advantages of asexual reproduction:

  • Mates not required.
  • The process of reproduction is rapid.
  • An enormous number of organisms can be produced in very less time.
  • Positive genetic influences pass on to successive generations.
  • It occurs in various environments.

Disadvantages of Asexual Reproduction

The major disadvantages of asexual reproduction are:

  • Lack of diversity. Since the offsprings are genetically identical to the parent they are more susceptible to the same diseases and nutrient deficiencies as the parent. All the negative mutations persist for generations.
  • Since only one organism is involved, the diversity among the organisms is limited.
  • They are unable to adapt to the changing environment.
  • A single change in the environment would eliminate the entire species.

Asexual Reproduction Examples

Following are the examples of asexual reproduction:

  • Bacterium undergoes binary fission in which the cell divides into two along with the nucleus.
  • Blackworms or mudworms reproduce through fragmentation.
  • Hydras reproduce through budding.
  • Organisms such as copperheads undergo parthenogenesis.
  • Sugarcane can be grown through vegetative propagation.

Let us study about sexual reproduction.

Sexual Reproduction

Sexual reproduction is a natural way of reproduction in humans, animals and the majority of plants also choose to reproduce sexually. This type of reproduction is more complex and lengthy as compared to asexual reproduction. Moreover, reproducing sexually gives the benefit of variation and off springs are unique. Sexual reproduction consists of a set of events and can be divided into three stages: Pre-fertilization, Fertilization, and Post-fertilization.

Stages of Sexual Reproduction

Pre-Fertilization
Modes of Reproduction | Science Class 10

This stage involves the events prior to fertilization. Gamete formation (gametogenesis) and transfer of gamete are the two processes that take place during this stage. Gametes are sex cells, which are haploid (23 chromosomes) in nature and are distinct in males and females. The male gamete is called sperm whereas female gamete is called ovum or egg. In every organism, these gametes are formed within special structures. Since female gamete is immobile, male gametes need to be transferred for fertilization.
In plants, this is attained by pollination. Unisexual animals transfer gametes by sexual intercourse.

Fertilization

Modes of Reproduction | Science Class 10

Once the haploid male and female gametes meet and fuse together to form a zygote, this is known as fertilization or syngamy. This can occur either outside the body called external fertilization or inside the body called internal fertilization.

Post-Fertilization

Modes of Reproduction | Science Class 10

Fertilization results in diploid zygote formation. Eventually, the zygote divides mitotically and develops as an embryo. This process is called embryogenesis. During embryogenesis, cell differentiates and modifies accordingly. Zygote development depends on the organism and its life cycle.
Modes of Reproduction | Science Class 10

Animals are classified into oviparous and viviparous based on whether the zygote develops outside or inside the body respectively. In angiosperms, the zygote develops into the ovary and ovary transforms into the fruit while ovules develop into seeds.

The document Modes of Reproduction | Science Class 10 is a part of the Class 10 Course Science Class 10.
All you need of Class 10 at this link: Class 10
78 videos|509 docs|153 tests

FAQs on Modes of Reproduction - Science Class 10

1. What is asexual reproduction?
Ans. Asexual reproduction is a mode of reproduction where an organism can produce offspring without the involvement of another organism. It does not require the fusion of gametes and the offspring are genetically identical to the parent.
2. What is sexual reproduction?
Ans. Sexual reproduction is a mode of reproduction where two organisms, typically of opposite sexes, come together to produce offspring. It involves the fusion of gametes, resulting in genetic variation in the offspring.
3. How does asexual reproduction occur?
Ans. Asexual reproduction can occur through various methods such as binary fission (splitting into two equal parts), budding (outgrowth on the parent organism), fragmentation (breaking into multiple pieces), or spore formation (releasing specialized cells capable of developing into new organisms).
4. What are the advantages of asexual reproduction?
Ans. Some advantages of asexual reproduction include rapid reproduction rate, no need for a mate, efficient utilization of resources, and the ability to colonize new environments quickly. It also ensures the offspring are genetically identical to the parent, which can be advantageous in stable environments.
5. What are the advantages of sexual reproduction?
Ans. Sexual reproduction allows for genetic variation in offspring, increasing the chances of survival in changing environments. It also promotes evolution by introducing new combinations of genes. Additionally, sexual reproduction can help eliminate harmful genetic mutations through the process of natural selection.
78 videos|509 docs|153 tests
Download as PDF
Explore Courses for Class 10 exam
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Download free EduRev App
Track your progress, build streaks, highlight & save important lessons and more!
Related Searches

mock tests for examination

,

Free

,

Sample Paper

,

video lectures

,

ppt

,

past year papers

,

Summary

,

MCQs

,

practice quizzes

,

pdf

,

Modes of Reproduction | Science Class 10

,

Modes of Reproduction | Science Class 10

,

Modes of Reproduction | Science Class 10

,

shortcuts and tricks

,

Exam

,

Previous Year Questions with Solutions

,

Objective type Questions

,

Viva Questions

,

study material

,

Semester Notes

,

Important questions

,

Extra Questions

;