Sexual Reproduction in animals

🌟Introduction:-

Sexual Reproduction is a process in which two parents(male and female) produces offspring by the fusion of gametes(sperm and eggs). Lets dive into the world of sexual Reproduction in details.

📚Key concept

Sexual Reproduction involves male and female gamete, leads to genetic variation in offspring. It occurs through meiosis and Fertilization. It is slower than the asexual Reproduction but allows evolution and diversity.

Basic steps:-

Gamete formation:-

• Male produces sperms(in testes)
• Female produces eggs/ova(in ovaries)
• Gametes are haploid(contains half the number of chromosome)

Fertilization:-

• Fusion of male and female gametes to form Zygote(diploid) is called fertilization.
• It can be of two types:-
• External Fertilization:- outside the body. Example:- Frog and fish
• Internal Fertilization:- inside the body. Example:- human and birds.

Zygote formation:-  

• Fertilized egg (zygote) undergoes cell divisions(mitosis) 

Embryo development:-

• Zygote becomes Embryo à develops organs à become foetus à grows into a baby.

Advantage of sexual Reproduction :-

• Creates genetic variation.
• Increase adaptation and survival.
• Removes harmful mutation over generation.

Why DNA does not get doubled in Sexual Reproduction?

Because gametes (sperm and egg) are formed by meiosis, which halves the chromosome number, so when thy fuses the original amount of DNA is restored, not doubled.