Renal Systemmmmmmmmmmm

• What is the main focus of the PHA115 lecture?

  Renal system
• What should students be able to explain about the urinary system?

  Organs and function of the urinary system
• What anatomical details of the kidney should students understand?

  Location, structure, blood supply, and function

  
• What is the nephron's role in the renal system?

  It is the structural and functional unit that forms urine
• What physiological processes should students understand in renal physiology?

  Urine formation, filtration, reabsorption, secretion, and regulation

  
• How are the kidneys shaped?

  Bean-shaped
• Where are the kidneys located?

  Along the back body wall below the diaphragm
• Why is the right kidney lower than the left?

  Because the liver occupies more space above it
• What percentage of cardiac output do the renal arteries deliver to the kidneys?

  ~1/4 (1200 ml)
• How does arterial and venous flow occur in the kidneys?

  They follow similar paths
• What type of nerve supply do the kidneys receive?

  Sympathetic fibers from the renal plexus
• What are the main functions of the kidneys?

  Removal of toxins, regulation of blood volume, and endocrine functions
• What is gluconeogenesis and when does it occur?

  It occurs during prolonged fasting
• What is the role of renin in the kidneys?

  Regulation of blood pressure and kidney function
• What does erythropoietin regulate?

  Red blood cell production
• What is the active form of vitamin D produced by the kidneys?

  1,25-dihydroxycholecalciferol (calcitriol)
• How many nephrons are there approximately in each kidney?

  ~1 million
• What are the two main components of a nephron?

  Renal corpuscle and renal tubule

  
• What percentage of nephrons are cortical nephrons?

  About 80–85%
• Where are the renal corpuscles of cortical nephrons located?

  In the outer portion of the cortex
• What type of blood supply do nephrons with short loops receive?

  From peritubular capillaries
• What percentage of nephrons are juxtamedullary nephrons?

  15–20%

  
• Where are the renal corpuscles of juxtamedullary nephrons located?

  Deep in the cortex, close to the medulla

  
• What type of blood supply do nephrons with long loops receive?

  From the vasa recta
• What do the distal convoluted tubules of several nephrons empty into?

  A single collecting duct

  
• What do collecting ducts converge into?

  Several hundred large papillary ducts
• What is the function of the glomerular capsule?

  Initial filtering component of the nephron
• What is the net filtration pressure in the glomerulus?

  $10 \text{ mmHg}$
• What hormones regulate glomerular filtration rate (GFR)?

  Angiotensin II and atrial natriuretic peptide (ANP)

  
• What effect does angiotensin II have on the arterioles?

  It is a potent vasoconstrictor

  
• What does ANP do to the glomerulus?

  Causes it to relax, increasing filtration area

  
• What are the two routes for sodium reabsorption in the nephron?

  Paracellular and transcellular reabsorption
• What is the primary function of the proximal convoluted tubule (PCT)?

  Reabsorption of sodium and other substances

  
• What is the role of the sodium-potassium pump in the nephron?

  Maintains sodium and potassium balance

  
• What does antidiuretic hormone (ADH) do in the kidneys?

  Increases water permeability in the collecting duct
• What does parathyroid hormone (PTH) stimulate in the kidneys?

  Reabsorption of calcium into the blood

  
• What does PTH inhibit in the proximal convoluted tubule?

  Reabsorption of phosphate (HPO4^2-)

  
• What is the summary of filtration, reabsorption, and secretion in the nephron and collecting duct?

  • Filtration occurs in the glomerulus
  • Reabsorption occurs in the proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct
  • Secretion occurs in the renal tubules

  
• What textbooks are recommended for further reading on renal physiology?

  • Ross and Wilson Anatomy and Physiology in Health and Illness
  • Gerard J. Tortora and Byran H. Derrickson Principles of Anatomy and Physiology
  • Frederic H. Martini Fundamentals of Anatomy & Physiology
  • Lauralee Sherwood Human Physiology From Cells to Systems
  • Robert G. Carroll Elsevier’s Integrated Physiology