Reproduction | Definitions, Characteristics And Types Of Asexual Reproduction

Reproduction

Reproduction

It is a biological process through which living organism produce offspring that are similar to themselves. It is one of the fundamental characters of organism. It is essential for the continuity of the species on the earth.

Types of Reproduction

  1. Asexual Reproduction / Somatogenic Reproduction / Agamogenesis 
  2. Sexual Reproduction

Definitions Of 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 parents. Asexual reproduction is observed in both multicellular and unicellular organisms.

Characteristics Of Asexual Reproduction

  1. It is uniparental.
  2. New individuals (progenies) develop directly from specialised or unspecialised parts of a single parent. Progenies are genetically and morphologically identical to each other and also similar to their parents. So progenies are called clone. Ramet is a single member of the clone.
  3. Meiosis, formation of gametes and fusion of gamete are absent.
  4. It is a quick method of reproduction.
  5. A very large number of individual can be produced by a parent.
  6. It occurs in lower organisms e.g. unicellular organism, simple plants & simple animals. Higher plants show vegetative reproduction (a type of asexual reproduction). 
NOTE: In asexual reproduction, formation of gametes may or may not occur but fusion of gametes never occur.

TYPES OF ASEXUAL REPRODUCTION

1. Binary Fission -

Parental cell divides into two daughter cells and each daughter cell grows into an adult.

e.g. Amoeba, Paramecium.

In Protists and Monerans, the organism or the parent cell divides into two to give rise to new individuals. Thus, in these organisms cell division is itself a mode of reproduction.

Binary Fission


2. Multi Fission -

Parental cell divides into many daughter cells. e.g. Amoeba, Plasmodium.

Fig.: Multiple Fission in Plasmodium
Multi Fission


3. Sporulation

In unfavourable condition, Amoeba produces a number of spores. The spore has resistant sheath called cyst wall. Spores are dispersed by air. Spore shows perennation (living for a long time). Under favourable conditions cach spore gives rise to a small Amoeba.
Sporulation

4. Fragmentation

An organism splits into fragments. Each of these fragments undergoes mitosis and develops into mature fully grown individual. e.g. some algae (Spirogyra), fungi, some annelids & sea stars.
Fragmentation

5. Budding-

(a) In yeast, the division is unequal and small buds are produced. The bud remains attached initially to the parent cell. Now this bud eventually gets separated and matures into new yeast organisms.

(b) In Hydra, the cells divide rapidly at a specific site and develop as an outgrowth called a bud. These buds, while attached to the parent body, develop into small individuals. When this individual becomes large enough, it detaches itself from the parent hody to exist as an independent individual.

Budding in Yeast
Budding in Hydra

FAQs

What is reproduction?

Reproduction is a biological process through which living organisms produce offspring that are similar to themselves. It is essential for the continuity of species on Earth.

What are the types of reproduction?

There are two main types of reproduction: asexual reproduction and sexual reproduction.

What is asexual reproduction?

Asexual reproduction is a mode of reproduction in which a new offspring is produced by a single parent. The offspring are genetically and physically identical to each other and to their parents.

What are the characteristics of asexual reproduction?

Asexual reproduction is uniparental, produces offspring directly from a single parent, and does not involve meiosis or the fusion of gametes. It is a quick method of reproduction that can produce a large number of individuals.

What are the different types of asexual reproduction?

The different types of asexual reproduction include binary fission, multifission, sporulation, fragmentation, and budding.

What is a binary fission?

Binary fission is a type of asexual reproduction where a parental cell divides into two daughter cells, each of which grows into an adult organism. Examples include amoeba and paramecium.

What is multi-fission?

Multifission is a type of asexual reproduction where a parental cell divides into many daughter cells. Examples include Amoeba and Plasmodium.

What is sporulation?

Sporulation is a type of asexual reproduction where an organism, like Amoeba, produces spores in unfavorable conditions. These spores have a resistant sheath and can persist for a long time until favorable conditions arise.

What is fragmentation?

Fragmentation is a type of asexual reproduction where an organism splits into fragments, and each fragment develops into a fully grown individual through mitosis. Examples include some algae, fungi, annelids, and sea stars.

What is budding?

Budding is a type of asexual reproduction where a small outgrowth develops on the parent organism and eventually detaches to become a new individual. Examples include budding in yeast and Hydra.