Tiêu đề 3. Reproduction in Organisms.pdf ✅

VIII - OLYMPIAD NEET BIOLOGY STUDY MATERIAL CDF-1 SEXUAL REPRODUCTION IN ANIMALS 1. The fusion of male and female gametes to produce new individual organism is called fertilisation. 2. Based on the fusion of gametes in the body, fertilization is of two types: i) External fertilization ii) Internal fertilization 3. Fertilization that takes place outside the body of the female is called external fertilization. Eg: Fish, Frog, and Starfish. 4. Fertilization which takes place inside the female body is called internal fertilization. Eg: Humans, Cow, Dog, and Hen. 5. Animals that give birth to young ones are called viviparous animals. Eg: Human, Cow and Dog. 6. Animals that lay eggs are called oviparous animals. Eg: Pigeon, Crow, and Hen. 7. External fertilization is very common in aquatic animals like fish, starfish, etc. 8. Transfer of characters from parents to off-spring in internal fertilization. 9. Animals carry both male and female reproductive organs are called hermaphrodites. Eg: Earthworm, Leeches 10. IVF – In-vitro fertilization (fertilization outside the body) babies born through this technique are called test-tube babies. 11. The transformation of the larva into adult through drastic changes is called metamorphosis. Eg: Frog. 12. The release of eggs and sperms into the water is known as spawning. 13. In 1978, Louise Brown was the first child successfully born through IVF. 14. The organisms which incubate their eggs inside their body are ovoviviparous organisms. Eg: Sharks and snakes 15. From the third month of pregnancy the embryo is called foetus. SYNOPSIS-1 SEXUAL REPRODUCTION IN ANIMALS Introduction 1. In animals and plants, reproduction is a necessary life process for continuation of species by producing off springs. 2. Animals and plants reproduce both sexually and asexually. Reproduction is one of the basic life processes.

VIII - OLYMPIAD NEET BIOLOGY STUDY MATERIAL 18. A layer of jelly holds the eggs together and provides protection to the eggs. 19. Male frog deposits sperms over them. 20. Sperms comes in contact with egg, results in fertilisation. This type of fertilisation in which the fusion of male & female gametes takes place outside the body of female is called external fertilisation. 21. We observe the different stages of frog starting from the egg to the adult stage. They are Egg ® Tadpole (larva) ® Adult. 22. The transformation of the larva into an adult through drastic internal and external changes is called metamorphosis. 23. Usually about 6-21 days after being fertilized the egg hatches. 24. Then, 7 to 10 days after the tadpole has hatched, it will begin to swim around and feed on algae. 25. After about 4 weeks, the gills start disappearing. Lungs develop in place of the gills. 26. Depending on water and food supply, by 12 to 16 weeks, the frog completes its full life cycle. Oviparous Animals 27. Oviparous animals lay eggs that develop and hatch into young individuals, but fertilization can be external or internal. But hatching always takes place in the external environment. 28. Oviparous animals can lay one or many eggs. 29. The animals hide their eggs in nests. Eg: Pigeon, Crow and Hen. Ovoviviparous Animals 30. The organisms which incubate their eggs inside their body are ovoviviparous organisms. These animals are born directly from the mother’s womb. Eg: Sharks and Snakes. Viviparous Animals 31. Viviparous is derived from the Latin word, vivus (living) and parus (to bear young ones) 32. Animals which give birth to their off springs/young ones are called viviparous. 33. The development of the embryo happens inside the body of the parent, eventually leading to the birth of a young one. 34. Viviparous animals feed their babies with their own milk. So they are called mammals. Eg: Human, Dog, and Cat. 35. Hermaphrodites: Hermaphroditism, is the condition of having both male and female reproductive organs in the same organism Eg: Earthworm, and Leech.