What Is a Gamete?
A gamete is a specialized reproductive cell, often called a sex cell, that contains half the genetic material of the parent organism. In sexual reproduction, two gametes fuse together in a process called fertilization to form a new individual.
Section 2: Haploid Nature of Gametes
The key characteristic of a gamete is that it is haploid, meaning it has only one set of chromosomes. This is in contrast to most other cells in an organism (somatic cells), which are diploid and contain two sets of chromosomes. Gametes are produced through a special type of cell division called meiosis, which reduces the chromosome number by half.
Section 3: A Practical Example
In humans and many other animals, there are two types of gametes. The male gamete is the sperm cell, which is typically small and motile. The female gamete is the egg cell, or ovum, which is much larger and non-motile. During fertilization, a sperm cell fuses with an egg cell to create a diploid cell called a zygote, which then develops into an embryo.
Section 4: Importance of Gametes
Gametes are essential for sexual reproduction and the promotion of genetic diversity. Because each gamete contains a unique combination of genes from the parent, their fusion creates a new organism with a genetic makeup different from both parents. This variation is a fundamental driver of evolution.