Excretory System

• Components of the excretory system

  Kidneys

  Nephrons

  Ureters

  Bladder

  Urethra

  Renal Artery

  Renal Vein
• Kidneys - Structure 


  Kidney shaped with an indentation known as the hilus.

  Divided into 3 main internal regions

  Made up of individual nephrons
• Kidney- Function


  Maintaining overall fluid balance

  Filtering waste materials from food/ medications or toxic substances
• Nephrons - Structure 


  Masses of tiny tubules

  Largely located in the medulla
• Nephrons- Function 


  Produces urine in the kidneys

  Regulated water/ soluble substances in blood

  Filters the blood of toxic substances

  Reabsorbing what is needed/ excreting the rest as urine
• Ureters - Structure 


  A hollow tube attached to each kidney

  Upper half of ureter is in the abdomen/ lower half is in pelvic area
• Ureter - Function


  Carry urine produced by the kidney to the bladder to be expelled from the body
• Bladder - Structure 


  Muscular organ that can expand and contract (epithelial tissue/ elastic)
• Bladder - Function 


  Temporary storage / collection of urine

  Expulsion of urine
• Urethra - Structure 


  A duct/ tube that is held closed by urethral sphincter

  A duct/ tube connected between bladder and external parts of reproductive organs- penis or vagina
• Urethra- Function


  Carries urine from the bladder to outside the body