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The terms “semen” and “sperm” are sometimes incorrectly used as synonyms. While they are closely connected, they are not the same.
Sperm is the male reproductive cell, or gamete; a microscopic cell made up of a head and tail and is a small portion of semen. The job of sperm is to fertilize the egg inside a woman’s body. To get the egg, sperm are carried by fluids that are produced by different male sex organs. This mix of fluids is called semen. Together, the seminal vesicles in the pelvis and the prostate provide chemicals in fluid that are beneficial to sperm. The average ejaculation for men is around a single teaspoon of fluid. This small amount can carry an incredible amount of sperm though: anywhere from 15 - 200 MILLION sperms.
Therefore, semen, or seminal fluid, is an organic fluid created in order to contain and transport sperm, or spermatozoa, from the male reproductive tract into the female reproductive tract. Semen contains a collection of substances that help the sperm survive, while also giving them a fluid or medium to swim in en route to the female egg, or ovum. This is a necessary step in order to fertilize an egg and create a zygote that can evolve and grow into a baby.
The purpose of sperm is to fertilize the female egg; the purpose of semen is to help the sperm make its way to the egg. In an extremely simplified sense, one can think of semen as the bus that sperm ride in order to get to work.
Nuts & Bolts: Semen vs. Sperm
To learn more about, please visit our series of posts about the male reproductive system:
Ovum - a mature female reproductive cell, especially of a human or other animal, which can divide to give rise to an embryo usually only after fertilization by a male cell.
Seminal fluid - another term for sperm.
Zygote - a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum.
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