Reproductive System PDF (MC1L AY 2021-2022)

Reproductive System MODULE 5 MC1L AY 2021 - 2022  Reproductive System MODULE 5 The reproductive system is unique. Most simply stated, its biological function is to pe...

Reproductive System MODULE 5 MC1L AY 2021 - 2022  Reproductive System MODULE 5 The reproductive system is unique. Most simply stated, its biological function is to perpetuate the species. The reproductive role of the male is to manufacture sperm and to deliver them to the female reproductive tract. The female, in turn, produces eggs. If the time is suitable, the combination of sperm and egg produces a fertilized egg. Once fertilization has occurred, the female uterus provides a nurturing, protective environment in which the embryo, later called the fetus, develops until birth. Human Male Reproductive System The primary sex organs: Testes – male gonads, lies in the scrotal sac; slightly lower than body temperature conducive for producing viable sperm – both an exocrine (sperm production) and endocrine (testosterone production) function A.) Epididymis – elongated structure running up the posterolateral aspect of the testis and capping its superior aspect which provides site for immature sperm to mature B.) Ductus deferens – also known as, “vas deferens” o Enclosed along with blood vessels and nerves in a connective tissue sheath called the spermatic cord C.) Seminal fluid – liquid medium in which sperm leaves the body D.) Penis – copulatory organ of the male designed to deliver sperm into the female respiratory tract a. Glans penis – enlarged tip at the end of the shaft b. Prepuce - foreskin ! Erection – event that causes the penis to be enlarged and rigid to serve as a penetrating device  Microscopic Anatomy of Testes and Sperm Testis - Tunica albuginea – dense connective tissue literally called, “white tunic” - Seminiferous tubules – sperm-forming factories - Rete testis – at the mediastinum of the testis; where the seminiferous tubules empty the sperm before traveling to the epididymis - Testosterone – the hormonal product of the testes Sperm During sperm formation, all excess cytoplasm is sloughed off the developing sperm. The remaining three (3) regions (Figure 27.3) are: ☞ Head – activating and genetic region; contains the DNA ☞ Midpiece – metabolic region ☞ Tail – locomotor Mature Sperm – streamlined cell equipped with an organ of locomotion that enables it to move long distances in jig time to get to the egg Human Female Reproductive System Primary sex organ Ovaries (female gonads) – both has exocrine (eggs, or ova production) and endocrine (estrogen and progesterone production) functions Eggs – female gametes Follicles – saclike structures where the egg develops - also produce estrogens Ovulation – event where that mature egg is ejected from the ovary Corpus luteum – converted ruptured follicle which secretes progesterone (and some estrogens)  Human Female Reproductive System The accessory structures of the female reproductive system transport, house, nurture, or otherwise serve the needs of the reproductive cells and/or the developing fetus. External genitalia Internal genitalia 1. External genitalia - consists of: a.Mons pubis - rounded fatty area overlying the pubic symphysis b.Labia majora - two elongated, hair-covered skin folds, that are homologous to the scrotum of the male c. Labia minora – two smaller hair-free folds d.Vestibule – oval area that contains the clitoris e. Clitoris – small protuberant erectile tissue, venous cavernous spaces, and specialized sensory corpuscles which are stimulated during sexual activity; homologous to male penis f. Perineum - the diamond-shaped region between the anterior end of the labial folds, the ischial tuberosities laterally, and the anus posteriorly g.Urethral orifice – outlet for the urinary system h.Greater vestibular glands (“Bartholin’s glands”) - pea-sized mucus-secreting glands which lubricates the vagina during intercourse 2. Internal genitalia – includes the vagina, uterus, uterine tubes, ovaries, and the structures that suspend these organs in the pelvic cavity (Figure 27.5) a. Vagina - extends for approximately 10 cm (4 inches) from the vestibule to the uterus superiorly; serves as a copulatory organ and birth canal and permits the menstrual flow to pass b. Uterus - pear-shaped muscular organ, situated between the bladder and the rectum which house the embryo or fetus i. Body – major portion of the uterus ii. Fundus – elastic upper portion of the uterus which accommodates most of the growing fetus c. Cervix – found at the narrow end of the uterus and in the upper portion of the vagina i. External os – lower cervical opening ii. Internal os – upper cervical opening Ligaments that supports the internal female organs: d.Fallopian tubes enter the superior part of the uterus and extend for about 10 cm (4 inches) toward the 1. Broad ligament - fold that encloses the uterine ovaries in the peritoneal cavity; site of fertilization tubes and uterus and secures them to the lateral body walls i. Ampulla – curved portion 2. Round and uterosacral ligaments – help attach ii. Infundibulum - funnel shaped portion uterus to the body wall iii. Fimbriae – funnel-shaped and 3. Ovarian ligament – supports the ovaries medially fingerlike projections that sweeps mature ovum from the ovary to the fallopian tube 4. Suspensory ligament – supports the ovaries laterally Microscopic study of an ovary Germinal epithelium: Outermost layer of the ovary Primary follicle: One or a few layers of cuboidal follicle cells surrounding the larger central developing ovum. Secondary (growing) follicles: Follicles consisting of several layers of follicle cells; Secrete estrogens. Vesicular (Graafian) follicle: At this stage, the follicle has a large antrum containing fluid. Corona radiata (radiating crown) – capsule of several layers of follicle cells Corpus luteum: A solid glandular structure containing a scalloped lumen that produces both estrogens and progesterone.