Anatomy and Physiology of the Male and Female Reproductive System

Focus on the complementary functions of male and female reproductive organs in reproduction.
The chapter is divided into parts focusing on male and female reproductive anatomy, physiology, and associated mechanisms.

An organized system with common anatomical components including the scrotum, testes, duct systems, penis, accessory glands, and external genitalia.

Scrotum:
- A pouch of skin and superficial fascia that suspends the testes outside the abdominal cavity.
- Important for maintaining testes at a temperature approximately 3°C lower than the core body temperature for optimal sperm production.
- Dartos Muscle: Smooth muscle that wrinkles the skin to minimize heat loss.
- Cremaster Muscle: Bands of mixed skeletal and smooth muscle that elevate the testes toward the body.

Structure:
- Surrounded by two layers:
- Tunica Vaginalis: The outer layer, two-layered.
- Tunica Albuginea: The inner fibrous capsule that extends inward to divide the testis into approximately 250 lobules.
- Each lobule contains seminiferous tubules where sperm production occurs.

Epididymis:
- Site for sperm maturation. It features stereocilia that aid in nutrient absorption and fluid retention.
- Sperm takes about 20 days to pass from head, through body, to tail of epididymis.
- Sperm can be stored for months and are propelled to the ductus deferens during ejaculation via peristaltic contractions.
Ductus Deferens (Vas Deferens):
- Ascends within the spermatic cord, through the inguinal canal, and into the pelvic cavity.
- Expands to form the ampulla on the posterior bladder wall, joining the duct of the seminal gland to form the ejaculatory duct.
- Thick smooth muscle layer needed for strong peristaltic waves during ejaculation.
- Vasectomy: Surgical procedure where the ductus deferens is cut and ligated to prevent sperm from entering the urethra.
Urethra:
- Serves both urinary and reproductive functions.
- Divided into three segments: Prostatic urethra (surrounded by prostate), intermediate (or membranous) urethra, and spongy urethra (opens to external environment).
- Urethral glands secrete mucus for lubrication prior to ejaculation.

Includes the seminal vesicles, prostate, and bulbo-urethral glands.
Seminal Glands: Produce an alkaline fluid that nourishes sperm and aids motility (fructose, citric acid, prostaglandins).
Prostate Gland: Contributes approximately 70% of semen volume; produces a fluid that activates sperm.
Bulbo-Urethral Glands: Provide lubrication for the glans and neutralize any acidic remainder in the urethra.

Milky-white fluid that contains sperm and secretions from glands.
Composition:
- Typically 2-5 ml is ejaculated with 20-150 million sperm per ml.
- Contains fructose, prostaglandins, enzymes, and antibodies to help sperm survive in the female tract.
- Alkalinity (pH 7.2–8.0) helps sperm survive in the acidic environment of the vagina.

The female reproductive system includes the ovaries, uterine tubes, uterus, vagina, and external genitalia (vulva).

Each ovary is almond-shaped and located lateral to the uterus.
Held in place by various ligaments:
- Ovarian Ligament: Anchors ovary to uterus.
- Suspensory Ligament: Anchors ovary laterally.
- Broad Ligament: Provides support by covering or “tenting” the uterus and associated structures.
Each ovary is surrounded by a fibrous tunica albuginea, covered by simple cuboidal epithelium.
Contains ovarian follicles where immature eggs reside, releasing an ovum during ovulation.

Function: Transport ovulated oocytes; common site for fertilization.
Structure includes three regions:
- Infundibulum: Funnel-shaped end with fimbriae.
- Ampulla: The site where fertilization typically occurs.
- Isthmus: Narrow region that connects to the uterus.

A muscular organ designed to support the fertilized egg.
Regions include:
- Body: The largest part.
- Fundus: Superior rounded region.
- Cervix: The lower part that opens into the vagina.
Cervical Canal: Contains glands with thick mucus that helps keep the uterus sterile and prevent sperm passage except during ovulation.

Comprised of three layers:
- Endometrium: The innermost layer that lines the uterine cavity, undergoing changes during the menstrual cycle.
- Myometrium: The muscular middle layer responsible for contractions during childbirth.
- Perimetrium: The outer layer.
Regeneration of the endometrium is influenced by ovarian hormones.

A distensible tube that functions as the birth canal and passageway for menstrual flow.
Layers include:
- Adventitia: The outer layer of connective tissue.
- Muscularis: Smooth muscle layer.
- Mucosa: Innermost layer lined with stratified squamous epithelium and contains rugae to stimulate during intercourse.

Comprises the mons pubis, labia majora, labia minora, clitoris, urethral orifice, and vaginal orifice.
The clitoris contains erectile tissue similar to the penis, contributing to sexual arousal.

Located within the breast, important for lactation.
Each gland contains lobes that open at the nipple; milk production occurs in glandular alveoli.

Include discussion questions related to reproductive anatomy and physiology.
Topics overview discussions on cancers related to the reproductive system to engage critical thinking and application of knowledge regarding diagnosis, treatment, and prevention strategies.

The organization and function of the male and female reproductive systems are crucial for understanding human reproduction and associated health issues.
Emphasis on collaborative learning and application through group activities fosters a deeper understanding of the subject matter.