Pronunciation: [ˈuːɡɐməs] (IPA) 
Oogamous is a scientific term that describes a type of sexual reproduction where the female produces larger, non-motile eggs, and the male produces smaller, motile sperm. The word is pronounced /oʊəˈɡeɪməs/ and is spelled with two 'o's and an 'a' in the middle. The 'oo' sound represents the long 'o' vowel sound, while the 'a' in the middle represents the short 'a' vowel sound. The 'g' is pronounced as a soft 'j' sound, as in "gel".
The term "oogamous" refers to a specific type of reproductive strategy found in certain organisms, particularly plants and some lower organisms such as algae or fungi. It describes the condition where two distinct gametes are involved in the reproductive process: a larger female gamete called the ovum or egg, and a smaller male gamete called the sperm.
In oogamy, the female gamete, or egg, is comparatively larger and immobile, while the male gamete, or sperm, is smaller, highly motile, and usually equipped with a flagellum for movement. This contrast in size and mobility between the two gametes is a defining characteristic of oogamous reproduction.
Oogamy typically occurs in organisms that reproduce sexually, where the union of the male and female gametes is necessary for fertilization to take place. The sperm is released by the male and actively swims towards the immobile egg, driven by chemical cues or signals. Once the sperm reaches the egg, it attaches and fertilization occurs, resulting in the formation of a zygote or embryo.
This reproductive strategy offers several advantages, such as increasing the chances of successful fertilization by ensuring the proximity of the gametes and preventing wasteful dispersion of the female gamete. Oogamy is commonly observed in many higher plants, such as angiosperms and gymnosperms, as well as various types of algae and fungi, where it contributes to the diversity and adaptation of these organisms.
In botany and protozoology, noting conjugation between dissimilar forms; opposed to isogamous.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word "oogamous" is derived from two Greek roots: "oós" meaning "egg" and "gámos" meaning "marriage" or "union". The term is used to describe a reproductive system in which two distinct types of gametes are produced: a larger non-mobile egg and a smaller mobile sperm. The fusion of these gametes during fertilization results in the production of zygotes.
