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Reproduction in Lower and Higher Animals — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYReproduction in Lower and Higher Animals3 Marks
Question
What is semen? Describe the composition of semen.
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Answer

$(1)$ Semen is the viscous, alkaline and milky fluid having $pH \ 7.2$ to $7.7$ ejaculated during sexual intercourse by male.
$(2)$ A single ejaculation of semen i.e. $2.5$ to $4 \ ml$ semen contains about $400$ millions of sperms.
$(3)$ Semen consists of sperms suspended in secretions of the epididymis and the accessory glands $($seminal vesicles, prostate gland and Cowper’s gland$).$ The semen nourishes the sperms by fructose, neutralizes acidity by $Ca^{++},$ ions and bicarbonates and also activates them for movement due to prostaglandins.

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