Transcript SPERMATOGENESIS - MBBS Students Club

By
Dr Samina Anjum
Male reproductive system
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Internal structure of testis
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The reproductive system of the male
Two major functions:
 Production of sperm
 To provide safe passage for spermatozoa
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Migration of primordial germ cells
(PGCs)
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Formation of Testis

First 6 weeks after conception, the gonads of
males and females are similar in appearance
(Indifferent stage).

If PGCs cells – Y chromosome (SRY gene)
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SPERMATOGENESIS

Is the sequence of events by which spermatogonia are
transformed into spermatozoa.

It begins at puberty.
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At Birth

PMGs are present in sex cords of testis
PMGs
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Puberty
Sex cords acquire
lumen & become
seminiferous tubules
 PMGs give rise to
spermatogonial stem
cells

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PHASES OF SPERMATOGENESIS
•
Spermatogonial Phase (Mitosis)
•
Spermatocyte Phase/Spermatocytosis
(Meiosis)
•
Spermatid Phase (Spermiogenesis)
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PHASE I-Spermatogonial Phase
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PHASE II-SPERMATOCYTOSIS
Spermatids
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PHASE II- MEOSIS
Prophase-22 days
Largest cell
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PHASE III-(SPERMIOGENESIS)
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Spermiogenesis Spermatocyte Spermatogonial
phase
Phase
phase
SPERMATOGENESIS
Cytokinesis is incomplete
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SPERMIOGENESIS
The series of changes resulting in the transformation of Spermatids into
spermatozoa
Formation of acrosome
Condensation of nucleus
Formation of neck, middle piece & tail
Shedding of most of the cytoplasm
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Mature Human Spermatozoa
Entire process of spermatogenesis takes approx. 74 days or 2 months
Approx. 300 millions sperms are daily produced.
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Sertoli cells
•Support
•Protect
•Nutrition
•Phagocytosis
•Regulate
spermatogenesis
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
Phagocytosis
of cytoplasm
by the Sertoli
cells.
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Epididymis
Storage
 Acquire motility

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Hormonal Regulation Of Male Reproductive
Function
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THANK YOU
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