oogamy

genetics

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July 1, 2026

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Oogamy is a form of sexual reproduction where one gamete is small and motile (the sperm), and the other is large and nonmotile (the egg). This is an advanced type of heterogamy, which is a reproductive process involving gametes that differ in form.1

In oogamy, the sperm fertilizes the egg, forming a zygote. The egg contains reserve material that supports the developing zygote. This process is observed in animals, some algae and fungi, and all higher plants. Genetics plays a role as gametes are haploid cells, meaning they contain half the genetic material needed to form a complete organism. During fertilization, these haploid gametes fuse to create a diploid zygote.21

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gamete
…advanced form of heterogamy called oogamy. In oogamy one of the gametes is small and motile (the sperm), and the other is large and nonmotile (the egg).
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…advanced form of heterogamy called oogamy. In oogamy one of the gametes is small and motile (the sperm), and the other is large and nonmotile (the egg).
Read More

plant reproductive system
The cellular basis
…sperm, is often designated as oogamy. In oogamous reproduction, the union of sperm and egg is called fertilization. Isogamy, heterogamy, and oogamy are often considered to represent an increasingly specialized evolutionary series.
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…sperm, is often designated as oogamy. In oogamous reproduction, the union of sperm and egg is called fertilization. Isogamy, heterogamy, and oogamy are often considered to represent an increasingly specialized evolutionary series.
Read More