Human Reproductive Systems PDF

# Male Reproductive System 1. **Located in the scrotum (sac of skin) between the upper thighs** 2. **Temperature is 96 degrees (maintain sperm viability)** 3. In the male fetus degrees (maintain near the kidneys and descend after birth * No descending - cryptorchidism 4. **Divided into lobe...

# Male Reproductive System 1. **Located in the scrotum (sac of skin) between the upper thighs** 2. **Temperature is 96 degrees (maintain sperm viability)** 3. In the male fetus degrees (maintain near the kidneys and descend after birth * No descending - cryptorchidism 4. **Divided into lobes** * Each contains its own seminiferous tubule (where sperm production takes place) * **Sustentacular cells** - located among seminiferous tubules; produce inhibin when stimulated by testosterone * **Interstitial cells** - also located the seminiferous tubules; produce testosterone when stimulated by LH * **Epididymis** - long coiled tube on the posterior of each testis * Maturation of sperm and functionality of flagella occur here * Uses smooth muscle to propel sperm into the ductus deferens * **Ductus deferens** - "vas deferens"; extends from the epididymis in the scrotum into the abdominal cavity through the inguinal canal * Smooth muscle layer contracts in peristaltic waves as part of ejaculation * **Ejaculatory duct** - receives sperm from the ductus deferens and secretion from the seminal vesicle of each teste * **Seminal vesicles** - behind the bladder * Secretion contains fructose to provide energy source for sperm * Alkaline (enhances sperm motility) * Each duct joins at the ductus deferens on each side to help form ejaculatory duct * **Prostate** - muscular gland below the urinary bladder * Surrounds the 1st inch of the urethra * Made of glandular tissue that secretes alkaline fluid (maintain sperm motility) * Smooth muscle contracts to contribute to expulsion of semen from urethra * Can become enlarged impairing urination start or flow; prostatectomy-sx removal of part or all of prostate * Cancer of prostate-2nd most common cancer among men * **Bulbourethral glands** - "Cowper's glands"; located below the prostate gland * Empties into the urethra * Produces an alkaline secretion (coats the inside of the urethra before ejaculation to neutralize acidic urine) * **Flow of Sperm/Semen** * Seminiferous tubules → rete testis (tubular network) → epididymis → ductus deferens (goes into the abdominal cavity through the inguinal canal up over the urinary bladder and behind it) → ejaculatory duct → urethra * Male Urethra - last duct the semen travels through before expulsion # Female Reproductive System 1. **Longest part** 2. **Extends through the external portion - penis** * Distal end of penis - glans penis * 3 masses of cavernous tissue * Blood sinuses * Connective tissue * Smooth muscle * When blood is minimal - penis is flaccid * During sexual stimulation, the arteries of the penis dilate, sinuses fill with blood, and penis becomes erect and firm to penetrate vagina (parasympathetic response) * Glans penis covered with skin - foreskin * Can be removed sx through circumcision 3. **Oogenesis** * Process of egg cell formation * Uses meiosis * Begins in the ovaries: * Pair of oval structures about 1.5 inches on either side of the uterus in the pelvic cavity * Broad ligament holds the ovaries in place * Regulated by hormones * FSH initiates - * Growth of ovarian follicles (contain oogonium - egg generating cells) * Several hundred thousand primary follicles present at birth * Only 300-400 will mature during childbearing years * Production begins at puberty * Continues throughout life until menopause * Several follicles will grow at the same time; whichever releases first will be ovulated, and others deteriorate * Each primary ovarian follicle contains an oocyte (potential egg) * Follicle cells surround the oocyte and secrete estrogen (matures egg (ovum)) * Produced every 28 days * A mature follicle is called a Graafian follicle * Will rupture to release the mature ovum * Influenced by LH * Called ovulation * Ruptured follicle then becomes the corpus luteum * Begins to secrete estrogen AND progesterone * Production is cyclical * **Fallopian tubes** * 4 inches long 4. **Have 2, one on each lateral end that enclose an ovary ** 5. **Fimbriae - fringelike projections that create currents in the fluid surrounding the ovary to pull the ovum into the fallopian tube** 6. **Medial end opens into the uterus** 7. **Smooth muscle creates peristaltic waves to keep the ovum moving toward the uterus ** 8. **Fertilization takes place here** 9. **If not fertilized, the ovum will die w/in 24-48 hours and disintegrate ** 10. **If fertilized, the ovum becomes a zygote and is swept into the uterus for implantation over 4-5 days** 11. **Ectopic pregnancy - embryo becomes implanted anywhere other than the uterus (i.e. fallopian tube, ovary, etc.); other places besides the uterus cannot sustain life for a prolonged period** # Uterus 1. **3 inches long, 2 inches wide** 2. **Above the urinary bladder and between the ovaries** 3. **Covered by the broad ligament ** 4. **5 Parts:** * **Fundus** - upper portion above the entry of the fallopian tubes * **Body** - large central portion * **Cervix** - opens into the vagina * **Myometrium** - smooth muscle layer that increases in size during pregnancy and contracts for labor and delivery * **Endometrium** - * **Basilar layer** - adjacent to the myometrium; vascular, permanent layer * **Functional layer** - regenerated and lost during the menstrual cycle * Influenced by estrogen and progesterone from the ovaries to increase blood vessel growth in preparation for pregnancy # Vagina 1. **Muscular tube, 4 inches in length** 2. **Extends from the cervix to the vaginal orifice in the perineum ** 3. **Behind the urethra but in front of the rectum** 4. **Partially covered by a thin membrane that is ruptured during sexual intercourse - hymen** 5. **Functions:** * Receive sperm from penis during sexual intercourse * Exit for menstrual flow * Birth canal at end of pregnancy 6. **Contains a normal bacterial flora - creates an acidic pH and inhibits growth of pathogens** # External Genitalia 1. "**vulva**" 2. **Includes:** * **Clitoris** - small mass of erectile tissue in front of the urethral opening for sexual stimulation * **Labia majora** - lateral pair of skin folds (outer folds) * **Labia minora** - medial pair of skin folds inside the labia majora * **Mons pubis** - pad of fat over the pubic symphysis covered with skin - pubic hair * **Vestibule** - area between the labia minora that contains the opening of the urethra and vagina * **Bartholin's glands** - in the floor of the vestibule; opens onto the mucous membrane of the vaginal opening; keeps the mucosa moist and lubricates vagina for sexual intercourse # Mammary Glands 1. **Produces milk for offspring** 2. **Glandular tissue surrounded by adipose tissue** 3. **Alveolar glands - produce milk after pregnancy** 4. **Enters the lactiferous ducts and meets at the nipple** 5. **Areola - skin around the nipple that is pigmented** 6. **During pregnancy, estrogen and progesterone prepare the glands for milk production** 7. **Oxytocin-stimulates the release of milk** 8. **Prolactin - makes the milk after pregnancy** # Menstrual Cycle 1. **3 phases:** * **Menstrual phase** * Loss of functional layer of endometrium (menstruation, menses) * Lasts 2-8 days w/average of 3-6 * Secretion of FSH is increasing * Several follicles begin to develop * **Follicular phase** * FSH stimulates growth of ovarian follicles and estrogen secretion by follicle cells (maturing of ovum) * LH secretion is increasing but slower * Estrogen stimulates blood vessel growth in the endometrium to regenerate the functional layer * Ends with ovulation (sharp increase in LH causes the rupture of the mature ovarian follicle) * **Luteal phase** * LH causes the ruptured follicle to become the corpus luteum (secretes inhibin (blocks secretion of FSH) and relaxin (inhibits contractions of the myometrium-helps with implanting)) causing estrogen AND progesterone to be secreted * Progesterone stimulates further growth of blood vessels in the endometrial functional layer and promotes storage of nutrients * As progesterone increases, LH decreases * If ovum is not fertilized, the secretion of progesterone decreases * Without progesterone, the endometrium cannot be maintained and will slough off * FSH begins to increase and the cycle begins again # Know the following terms: 1. **Renal medulla:** Inner layer composed of loops of Henle and collecting tubules 2. **Renal cortex:** Outer layer contains renal corpuscles and convoluted tubules * Contains wedge-shaped structures called renal pyramids (triangular segments) 3. **Renal pelvis:** Apex of each pyramid, an expansion of the ureter within the hilus of the kidney * Calyces are funnel-shaped expansions of renal pelvis (medial aspect of kidney) 4. **Glomerular filtration rate:** Total volume of renal filtrate that the kidney forms in 1 minute, average 100-125 mL/min 5. **Ectopic pregnancy:** Implantation of fertilized egg outside of uterus * Commonly in the fallopian tube (ovary or abdomen) * Often results in death of embryo b/c functional placenta cannot be formed in abnormal locations 6. **Fundus:** Upper portion above the entry of the fallopian tubes 7. **Clitoris:** Small mass of erectile tissue anterior to the urethral orifice 8. **Menstruation:** Periodic discharge of bloody fluid from the uterus that occurs at regular intervals from puberty to menopause. 9. **Prostatectomy:** Surgical procedure to remove prostate gland 10. **Prostatic hypertrophy:** Enlargement of the prostate gland; May be benign or malignant.