What are the basic steps in sexual reproduction?

Sexual reproduction involves the fusion of male and female gametes, followed by fertilisation, embryonic development, and birth or hatching.

Sexual reproduction is a biological process that involves two parents to produce offspring. It begins with the production of gametes, or sex cells, through a process called meiosis. In males, the gametes are called sperm, and in females, they are called eggs or ova. These gametes contain half the number of chromosomes of a normal cell, which means they are haploid.

The next step is the fusion of these gametes, a process known as fertilisation. This usually occurs within the female's body. The sperm cell travels to the egg cell and penetrates its outer layer, combining their genetic material. This results in a zygote, a single cell with a full set of chromosomes, which is now diploid.

The zygote then begins to divide and grow through a process called mitosis, forming an embryo. This embryonic development involves a series of cell divisions and differentiations, where cells start to specialise into different types of cells, tissues, and organs. This process is guided by the genetic information inherited from both parents.

Finally, the embryo develops into a fully formed organism. In mammals, this involves a gestation period within the mother's womb, followed by birth. In other organisms, such as birds or reptiles, the embryo develops within an egg that is laid and later hatches.

In summary, sexual reproduction is a complex process that involves the production and fusion of gametes, followed by fertilisation, embryonic development, and the birth or hatching of a new organism. This process ensures the mixing of genetic material from two parents, leading to offspring with unique combinations of traits.