Functions of the Kidneys

• Blood Filtration
  • Removal of Waste: The kidneys filter waste products from the blood.
  • Excess Fluids: Filters out excess fluid to maintain fluid balance.
  • Ion Regulation: Adjusts concentrations of ions as needed.

Anatomy of the Urinary System

• Kidneys
  • Right and Left Kidney: Left kidney is on the left side of the body, right on the right.
  • Ureters: Tubes that transport urine from the kidneys to the bladder (one from each kidney).
  • Urinary Bladder: Stores urine until excretion.
  • Urethra: Final pathway for urine to exit the body.
  • Length Differences: Female urethra is about a few centimeters long; male urethra is much longer and has two sphincters.
  • Sphincter Types: Internal urethral sphincter (smooth muscle) and external urethral sphincter (skeletal muscle).
  • UTIs in Females: Susceptibility due to shorter urethra and proximity to the anus.

Structure of the Kidney

• Renal Vasculature

  • Renal Artery: Brings oxygenated blood to the kidney (red).
  • Renal Vein: Takes deoxygenated blood away from the kidney (blue).

• Hilum: Indentation area where the renal artery, renal vein, and ureter enter/exit the kidney.

• Capsule: Protective outer layer of the kidney.

• Cortex and Medulla

  • Cortex: Outer region of the kidney (light color).
  • Medulla: Inner region, contains renal pyramids and renal columns.

• Renal Pyramids and Columns

  • Renal Pyramids: Structures within the medulla where urine concentration occurs.
  • Renal Columns: Tissues between the renal pyramids that contain blood vessels.

• Collecting Urine

  • Renal Papilla: Area at the tip of the renal pyramid where urine drains into the minor calyx.
  • Minor Calyx: Collects urine from renal papillae.
  • Major Calyx: Formed from merging minor calyces, leading to the renal pelvis.
  • Renal Pelvis: Funnel-shaped structure that channels urine into the ureter.

Female Reproductive System

• Anatomy Overview

  • Ovaries: Produce eggs (ova).
  • Fimbriae: Finger-like projections that guide eggs into fallopian tubes.
  • Fallopian Tubes: Site of fertilization.

• Uterus Structure

  • Regions: Fundus (top), body (main part), cervix (opening to the vagina).
  • Layers:
  • Endometrium: Inner mucosal lining.
  • Myometrium: Muscular layer that contracts during labor.

• Vagina: Birth canal, features rugae to allow expansion during childbirth.

• External Female Anatomy:

  • Mons Pubis: Fatty area over the pubic bone.
  • Labia Majora & Minora: Folds of skin protecting the vagina.
  • Clitoris: Erectile tissue, homologous to the male penis.
  • Vaginal Opening: Entrance to the vagina.

Male Reproductive System

• Anatomy Overview

  • Scrotum: Houses the testes; regulates temperature for sperm production.
  • Testes: Produce sperm cells.
  • Epididymis: Stores mature sperm cells.

• Sperm Pathway

  • Vas Deferens: Tube that transports sperm from the epididymis.
  • Prostate Gland: Secretes fluids that nourish sperm.
  • Urethra: Final pathway for sperm and urine to exit the body.

• Erectile Tissue:

  • Corpus Spongiosum: Surrounds the spongy urethra; maintains urethra openness during erection.
  • Corpus Cavernosum: Fills with blood during arousal to cause erection.

• Temperature Regulation:

  • Cremaster and Dartos Muscles: Adjust the position of the testes based on temperature to keep sperm viable.