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Found Sperm 122 times.

Displaying results 1 to 10.

1. Acroblast
A granule within the young sperm cell (a spermatid ) that eventually becomes the acrosome or caplike frontal portion of the mature sperm cell.

2. Acrosin
An enzyme found in sperm cells which is thought to help the sperm penetrate the tough outer surface of the ovum .

3. Acrosome
A membrane-bound section at the tip of the head of a sperm which contains lytic enzyme s (hyaluronidase in mammalian sperm) which break down the outer coat of the egg and allow the sperm to inject its haploid DNA .

4. Acrosome
Anterior membrane-bound compartment covering the sperm head that contains lytic enzyme s, which help the sperm digest through the tough outer surface of the egg . The compartment is secreted by the Golgi apparatus of the spermatid (young sperm cell).

5. Acrosome reaction
A chemical change that enables a sperm to penetrate an egg .

6. Adaptive radiation
The development of a variety of species from a single ancestral form; occurs when a new habitat becomes available to a population . Evolutionary pattern of divergence of a great many taxa from a common ancestral species as a result of novel adaptations or a recent mass extinction . Examples: mammals during the Cenozoic Era after the extinction of dinosaurs at the close of the Mesozoic Era flowering plants during the Cretaceous Period diversified because of their reproductive advantages over gymnosperm and non-seed plants that dominated the floras of the world at that time.

7. Agameon
An organism that reproduces asexually only, without producing gamete s ( sperm or egg s).

8. Aleurone (aleuron)
These are granules of protein found in the top cell layer of the endosperm of grains such as wheat.

9. Androgenetic merogony
The development of an egg fragment that has been fertilized by sperm but has no nuclei from the egg.

10. Andrologist
A medical specialist who treats sperm problems.


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