Reproduction in Plants and Animals

Meaning of Reproduction

Reproduction is the biological process by which living organisms produce new individuals of their own kind, ensuring the continuity of a species.

Types of Reproduction

• Asexual reproduction – involves only one parent and no fusion of sex cells; offspring are genetically identical to the parent
• Sexual reproduction – involves the fusion of a male sex cell (gamete) and a female sex cell to form a new individual with genetic variation

Reproduction in Plants

• Asexual methods – vegetative propagation using stems (cuttings), roots, leaves or runners
• Sexual reproduction – occurs in flowers through pollination (transfer of pollen from anther to stigma) followed by fertilisation, leading to seed and fruit formation
• Pollination may be self-pollination (within the same flower) or cross-pollination (between different flowers), carried out by agents such as wind, insects, water or animals

Reproduction in Animals

• Asexual methods – budding (e.g. hydra) and binary fission (e.g. amoeba)
• Sexual reproduction – the male produces sperm and the female produces eggs (ova); fertilisation may be external (as in most fish and frogs) or internal (as in mammals, birds and reptiles)

Importance of Reproduction

Reproduction replaces organisms that die, maintains population size, and (in sexual reproduction) introduces variation that helps species adapt and survive changing conditions.

Summary

Whether in plants or animals, reproduction ensures that life continues from one generation to the next, using either asexual or sexual methods depending on the organism.