BIOLOGY- REPRODUCTION IN ORGANISM Part 4

BIOLOGY- REPRODUCTION IN ORGANISM Part 4

Biology: Reproduction in Organisms – Part 4

Reproduction in Organisms

Reproduction is a biological process by which organisms produce their offspring. It ensures the continuity of species.

Part 4: Sexual Reproduction in Organisms

1. What is Sexual Reproduction?

Sexual reproduction involves the fusion of male and female gametes (sperm and egg) to form a zygote, which develops into a new organism.

• Biparental Inheritance: Involves two parents.
• Genetic Variation: Offspring show variations due to recombination of genes.

2. Phases of Sexual Reproduction:

1. Pre-fertilization Events:

   • Gametogenesis: Formation of male and female gametes.
     • Isogamy: Similar gametes (Algae).
     • Anisogamy: Dissimilar gametes (Humans).
   • Gamete Transfer: Transfer of gametes for fertilization.

2. Fertilization (Syngamy):

   • External Fertilization: Fusion occurs outside the body (Fishes, Amphibians).
   • Internal Fertilization: Fusion occurs inside the body (Reptiles, Mammals).

3. Post-fertilization Events:

   • Zygote Formation: Fusion of sperm and egg forms a zygote.
   • Embryogenesis: Development of the embryo from the zygote.

3. Types of Organisms Based on Reproduction:

• Oviparous: Egg-laying organisms (Birds, Reptiles).
• Viviparous: Give birth to young ones (Humans, Mammals).
• Ovoviviparous: Eggs hatch inside the mother’s body (Some Sharks).

4. Importance of Sexual Reproduction:

• Creates genetic diversity.
• Helps in adaptation and evolution.
• Reduces the accumulation of harmful mutations.

5. Examples of Sexual Reproduction:

• Plants: Pollination and fertilization lead to seed formation.
• Animals: Fertilization between sperm and egg.

 Quick Quiz:

1. What is the difference between isogamy and anisogamy?
2. Name one oviparous and one viviparous animal.
3. Why is genetic variation important in sexual reproduction?

अगर आपको किसी और टॉपिक या डिटेल्स में जाना है तो बताइए!

BIOLOGY- REPRODUCTION IN ORGANISM Part 4

CHAPTER – How do Organisms Reproduce?

Reproduction-in-organisms.pdf

NCERT-Class-12-Biology.pdf

REPRODUCTION AND POPULATION CONTROL