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Explore the process of spermatogenesis and oogenesis in male reproductive system, including hormonal regulation, semen production, and sperm morphology. Learn about the cells involved and hormonal influences on germ cell development. Study the anatomy and functions of sperm cells.
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Applied Developmental Biology Dr. Lubna Tahtamouni The Hashemite University 23/2/2009 Week # 3 Spermatogenesis 1
Male Reproductive System • Production of: • Semen • Hormones
Semen • 5% Sperm • 2. 65% Secretions of seminal vesicles: • proteins, enzymes, mucus, fructose, prostaglandins • 3. 30% secretions of prostate glands: • milky alkaline fluid, high in basic sugars, pH ~ 7.3-8
Cross Section through Testis • Cells in spermatogenesis: • Spermatogenic cells • Sertoli cells • Leydig cells
prominent euchromatic nucleus and prominent nucleolus- cell sends processes around developing germ cells making cell margins difficult to • observe at LM level • inter-Sertoli cell tight junctions at the base of the tubule form blood testis barrier • - synthesizes and secretes a fluid into the lumen containing: • 1. androgen binding protein (ABP) that binds testosterone and creates increased (total) • concentration of testosterone • - secretion of ABP stimulated by FSH and testosterone • 2. inhibin that suppresses FSH secretion from pituitary • provides environment for germ cell development (nurse cell) • phagocytose and digest shed residual bodies produced by developing germ cells
interstitial cells of Leydig (Leydig cells): - steroid-synthesizing cell with enriched sER and mitochondria- produce and secrete testosterone- stimulated by LH and prolactin from pituitary
Spermatogenesis Spermatocytogenesis Meiosis Spermiogenesis
The shape of a human sperm cell is adapted to its function Middlepiece Neck Head Plasma membrane Tail Mitochondrion(spiral shape) Nucleus Acrosome
Semen value Volume Concentration Motility Morphology Normal range > 2.0ml > 20 million/ml > 40% motile >14% Semen Analysis – reference values