The Urinary and Reproductive Systems: The Final Structures

So you have finally made it to the final week of anatomy!!! Hooray!!! You are now all masters of the human body, or at least close to it. So now what do you do? Well, you first master this last week of terms and then study, study, STUDY for the final examination. Remember it is only two weeks away, so get right on top of it!!! I am confident you will all do great as you keep to your studies and study a little bit every day.

This week is just full of fun and interesting structures. The Urinary and Reproductive systems are complete miracles when you ponder what they can accomplish. What man-made system do you know, that can bring life into the world? What man-made system do you know of that can filter 440 gallons of blood each day without breaking down? There is none!! That is why the human body is the perfect creation because there is nothing in the world that can compare to it. Every time I think about the divinity of our bodies, I am reminded of an ever loving Heavenly Father who created these bodies in the first place so that we could have a fullness of joy.

Now, here are a few clarifications and ways to remember this week's terms...

The Urinary System

Hilus: Portion of the kidney where blood vessels, nerves and ureter enter and exit.

Cortex: Most superficial layer of the kidney. Structures within the cortex are...

• Glomerulus
• Proximal Convoluted Tubule
• Distal Convoluted Tubule

Medulla: Most deep layer of the kidney. Structures within the cortex are...

• Renal Pyramids
• Nephron Loop
• Collecting Ducts

Papilla: Tip of the Renal Pyramid

Minor Calyx: region extending from the papilla

Major Calyx: Joining of two or three minor calyx

Renal Pelvis: Joining of two or three major calyx

Ureter: Structure that carries urine to the bladder. Begins when the renal pelvis becomes uniform shaped.

Internal Urethral Sphincter: Found inferior to the bladder; prevents urine from leaving the bladder and entering the urethra.

External Urethral Sphincter: Voluntary muscle found at the urogenital diaphragm; inability to control results in a condition call incontinence.

The Female Reproductive System

Ovary: Found lateral to the uterus and produce ova(eggs) and secrete estrogen and progesterone

Fimbrae: Ciliated projections that cover the lateral portion of the ovary; receive the ova when it is released

Uterus: Three layered sack

1. Perimetrium: Most superficial layer; visceral peritoneum
2. Myometrium: Thick middle layer; composed of smooth muscle
3. Endometrium: Inner mucosal layer; place of implantation (two layers)
   

• Stratum Functionalis: layer that degenerates during menstruation
• Stratum Basalis: layer that builds up the endometrium (stratum functionalis) and prepares for implantation.

Fundus: Rounded, superior portion of the uterus

Cervix: Narrow, inferior portion of the uterus

External Os: opening of the uterus to the vagina; dilates during fetal delivery

Vagina: Tube inferior to the unterus; lies posterior to the urethra and anterior to the anus

• Fornix: superior portion of the vagina; surrounds the cervix
• Vaginal Rugae: ridges of the internal vaginal lining; permit stretching of the birth canal
• Vaginal Orifice: external opening of the vagina
• Vestibular Glands: pea shaped glands located on each side of the vagina; found deep to the labia majora

Vulva: Triangular shaped region consisting of...

• Mons Pubis: fatty tissue laying over the symphysis pubis
  
• Labia Majora: found lateral to the vaginal opening and continuous with the mons pubis
  
• Labia Minora: medial to the labia minora
• Clitoris: tissue found anterior to the urethral orifice
  
• Vestibule: space enclosed by labia minora; contains the vaginal and urethral openings

Perineum: Diamond shaped region containing the anal, vaginal and urethral openings

Breast: gland of milk secretion

• Mammary Glands: secretory structures
• Lactiferous Duct: passageway of milk from the mammary gland to the nipple

The Male Reproductive System

Scrotum: compartment external to the pelvic cavity; supports and protects the testes.

• Median Septum: Divides the scrotum into two compartments, one for each testis; serves as a protection shield if one testis becomes infected or cancerous.
• Dartos Muscle: smooth muscle found in the inner wall of the scrotum; functions to keep the testes three degrees below normal body temperature
• Cremaster Muscle: Skeletal muscle found deep to the dartos muscle; continuous with the internal abdominal oblique.

**Tennis Ball Analogy

• Tennis ball: Testis
• Tennis ball in sock: Dartos muscle
• Hand under sock: Cremaster muscle
  

Testis: paired oval shaped organ; sperm and hormone production

• Tunica Albuginea: Fibrous connective tissue layer that directly covers the testes
• Seminiferous Tubules: coiled sperm producing tubes within the lobes of the testis
• Efferent Ductules: take sperm from the seminiferous tubules to the epididymis

Epididymis: place where sperm mature; learn how to swim; "Swimming School"

Spermatic Cord: Cord composed of ductus deferens, cremaster muscle, testicular arteries, veins and nerves

Seminal Vesicle: secretes fructose to give sperm energy; lunch booth

Ejaculatory Duct: one inch long tube; formed by the union of the ductus deferens and seminal vesicle

Prostate Gland: lies inferior to the bladder

Bulbourethral Gland: lies inferior to the prostate; secretes mucus into the urethra

Urethra: Three separate areas...

• Prostatic Urethra: part that passes through the prostate
• Membranous Urethra: part that passes through the urogenital diaphragm
• Spongy Urethra: last and longest part that is located in the body of the penis

**Think P.M.S to remember these structures in order

Glans: enlarged terminal portion of the penis

Prepuce: continuous skin covering of glans; also known as the foreskin; removed by circumcision

Body of Penis: composed of three chambers of erectile tissue

• Corpora Cavernosa: paired columns
• Corpus Spongiosum: tissue that surrounds the spongy urethra
• Dorsal Veins: drain blood from the penis
• Deep Arteries: one locate in each corpora cavernosa; supply erectile bodies with blood
  

**So there you have it!!! With these notes and your dedication to the ol' anatomy open lab, you will be masters in no time of the urinary and reproductive systems. Don't miss out on the mock quiz in lab next week. It will be very much worth your time and energy. Good luck and happy studying!!!