Describe how the mammalian male reproductive system is adapted to performing its function. (20 mks)

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Describe how the mammalian male reproductive system is adapted to performing its function. (20 mks)
-Have the penis which is highly vascularized /spongy; which becomes erect when filled with blood; to allow entry into the vagina;
-Penis also has sensitive glans for sensitivity; facilitating erection/ projection.
-Scrotum; contains testicles outside the body; providing a cooler environment for sperm production and storage.
-Scrotum similarly protects the testicles from external mechanical damage.
-Testes contain numerous seminiferous tubules, on whose walls spermatogenesis occurs; the process is favoured by lower temperatures.
-Testes contain sertoli cells, which nourish sperms until they are mature.
-Tube system; have epidydimis that coil;to fit within a small space and for storage of sperms, have vas deferens lined with smooth mucles whose contraction pushes sperms out and allows ejaculation.
-Has many primordial germ cell hence gametes are produced in large numbers; to increase chances of fertilization.

-The resultant male gametes, sperms have a tail and abundant mitochondria in the middle sheath to provide energy and allow swimming to reach the egg.
-Seminal vesicles and prostrate glands; produce seminal fluid to provide medium/nutrient for sperms to swim in;
-Secretions of seminal vesicles contain sucrose and prostaglandins
-Sucrose provides a source of energy for the sperm cells;
-Prostaglandins act as a chemical signal in the female system, triggering the rhythmic contraction of smooth muscle along the reproductive tract;
-Prostrate glands secret an alkaline buffer that protects sperm cells against the acidic environment of the vagina;
-Cowper’s glands secrete mucus, to lubricate the tube system, and allow easy and efficient swimming of sperms.
-Have sphincter muscles at the opening of the bladder and sperm ducts into the urethra; to ensure urine and sperms don't pass out at the same time.
Total = 30 marks; maximum score = 20 marks

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