Kidneys

• What is the excretory system responsible for?

  Removing metabolic wastes and maintaining osmotic balance
• What are the two major obstacles the excretory system addresses?

  Osmotic balance and metabolic waste removal
• What is a major nitrogenous waste produced by the liver?

  Urea
• Which organs are involved in the excretory system?

  Skin, liver, lungs, and kidneys
• How many kidneys are in the human body?

  Two
• What is the function of the bladder?

  To hold urine before excretion
• What is the role of ureters in the excretory system?

  To drain urine from kidneys to bladder
• What is the nephron's primary function?

  To process waste products and create urine
• What is the glomerulus?

  A specialized mass of capillaries in the nephron
• What is the fluid called once it enters the Bowman’s capsule?

  Filtrate
• What major components are found in the filtrate?

  Water, glucose, amino acids, salts, urea
• What happens to some filtrate in the nephron?

  It is reabsorbed back into the body
• How do substances move in and out of the nephron?

  By diffusion, facilitated diffusion, and active transport
• What does the proximal tubule do?

  Reabsorbs NaCl, water, glucose, and amino acids
• What is the role of aquaporins in the loop of Henle?

  Facilitating water reabsorption
• What occurs in the ascending limb of the loop of Henle?

  NaCl is reabsorbed, but water cannot exit
• What substances are secreted in the distal convoluted tubule?

  H+, ammonium, and potassium ions
• How is the permeability of the collecting duct regulated?

  By hormonal control
• What happens to urine concentration when a person is dehydrated?


  Urine becomes very concentrated
• What are diuretics used for?

  To increase urine production
• What is dialysis used for?

  To filter blood in compromised kidney function
• What is a nephrologist?

  A doctor specializing in kidney function
• What are the main components and functions of the nephron?

  • Functional unit of the kidney
  • Components: glomerulus, Bowman’s capsule, proximal tubule, loop of Henle, distal convoluted tubule, collecting duct
  • Functions: filtration, reabsorption, secretion, urine formation
• What is the main function of the kidney?

  Excretion of metabolic waste
• How do the organs of the excretory system interact with other body systems?

  • Skin: part of the integumentary system
  • Liver: accessory organ in the digestive system
  • Lungs: organs of the respiratory system
  • All systems work together for homeostasis
• What is excretion?

  Removal of waste products of metabolism
• Which organ excretes carbon dioxide?

  Lungs
• What waste product does the kidney excrete?

  Urea
• How many kidneys do humans typically have?

  Two
• Where are the kidneys located in the body?

  Bottom of the back
• What is the outermost layer of the kidney called?

  Cortex
• What is the middle layer of the kidney known as?

  Medulla
• What is the role of the renal pelvis?

  Holds everything in place
• What does the renal artery do?

  Supplies oxygenated blood to the kidney
• What is the function of the renal vein?

  Removes deoxygenated blood from the kidney
• What does the ureter do?

  Carries urine to the bladder
• What is the urethra's function?

  Transports urine out of the body
• What are nephrons?

  Tiny structures in the kidney
• What is the glomerulus?

  A capillary network in the nephron
• What is ultrafiltration?

  Process of forcing small molecules out of blood