from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun Any of the cells that give rise through mitosis to the spermatocytes and are found in the testes of vertebrates.
from The Century Dictionary.
- noun In botany, same as
- noun A primitive or formative seminal cell, forming a kind of sperm-morula, or spermosphere composed of spermatoblasts or spermatocytes, which in turn give rise to spermatozooids.
from the GNU version of the Collaborative International Dictionary of English.
- noun (Physiol.) A primitive seminal cell, occuring in masses in the seminal tubules. It divides into a mass (spermosphere) of small cells (spermoblast), which in turn give rise to spermatozoids.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun biology Any of the
undifferentiated cellsin the male gonadsthat become spermatocytes; a spermatoblast
from The American Heritage® Dictionary of the English Language, 4th Edition
When a spermatogonium was observed to change to a primary spermatocyte-still diploid-it would be segregated and at the instant it divided into two secondary spermatocytes-haploids, one with an X chromosome and one with a Y chromosome-they would be again segregated and each would be encouraged to develop into spermatozoa. \par
Difference Between spermatogenesis and Spermiogenesis • Spermatogenesis is the complete process of formation of spermatozoon from a spermatogonium.
The symbols used are: spermatogonium (white pentagon); primary spermatocytes (white stars); round spermatids (white asterisk); elongated spermatids with high polarization, indicating the residual body or axonemal region (black asterisk) and the heads (white arrowheads).