Kidneys

• What is the main role of the kidneys?

  To filter blood and remove waste
• What is the main waste product filtered by the kidneys?

  Urea
• How is urea produced in the body?

  Through deamination of excess amino acids
• Why is it important to regulate ion levels in the body?

  To prevent cell damage and maintain function
• What ions do we commonly get from our diet?

  Sodium and potassium ions
• How do we lose ions from our body?

  Primarily through sweating
• What is the main way the body regulates water levels?

  Through the kidneys in urine production
• What happens to cells when there is too much water in the body?

  They swell and may burst
• What is the process called where the kidneys filter blood?

  Filtration
• What is selectively reabsorbed in the kidneys?

  Glucose, some water, and ions
• What is the process of selective reabsorption in the kidneys?

  • Reabsorption of useful substances
  • Glucose is fully reabsorbed
  • Some water and ions are reabsorbed
  • Urea is not reabsorbed
• What structure in the brain detects water concentration in the bloodstream?

  The hypothalamus
• What hormone is released by the pituitary gland to regulate water levels?

  ADH (antidiuretic hormone)
• What effect does ADH have on the kidneys?

  It increases water reabsorption
• What happens when water levels in the bloodstream are too high?

  Less ADH is released
• What is a negative feedback loop in water regulation?

  • Body monitors water levels
  • Adjusts levels to maintain balance
  • Increases reabsorption when low
  • Decreases reabsorption when high
• What is the overall goal of kidney function regarding waste and water?

  To maintain balance and remove waste
• What are the three main roles of the kidneys?

  Remove waste, regulate ions, regulate water
• What waste product do the kidneys remove from the blood?

  Urea
• How does blood flow through the kidneys?

  In through renal arteries, out through renal veins
• What do the kidneys produce from filtered blood?

  Urine
• What structure stores urine until it is excreted?

  Bladder
• What is the pathway of urine from the kidneys to excretion?

  Kidneys → Ureters → Bladder → Urethra
• What is the first step in urine formation?

  Filtration in the glomerulus
• What is the glomerulus?

  A tangle of blood vessels
• What is Bowman's capsule?

  The start of the nephron tubule
• What substances can be filtered into Bowman's capsule?

  Water, amino acids, urea, glucose, ions
• What percentage of plasma is filtered through to Bowman's capsule?

  About 20 percent
• What happens to the fluid after it is filtered?

  It passes along the tubules for reabsorption
• What is selective reabsorption?

  Reabsorbing useful substances back into blood
• Which substances are almost completely reabsorbed?

  Glucose and amino acids
• What is the process that occurs throughout the nephron tubule?

  Selective reabsorption
• What are the parts of the nephron in order?

  1. Glomerulus
  2. Bowman's capsule
  3. Proximal convoluted tubule
  4. Loop of Henle
  5. Distal convoluted tubule
  6. Collecting duct
• What happens to fluid that passes out of the collecting duct?

  It is classed as urine
• What is the final destination of urine after leaving the kidneys?

  Ureter
• What is the role of the ureters?

  To transport urine to the bladder
• What is the function of the urethra?

  To release urine from the body
• Why is understanding kidney anatomy important?

  To comprehend urine formation processes
• What is kidney failure?

  When kidneys suddenly stop working
• What happens to waste substances in kidney failure?

  They build up in the bloodstream