Human Physiology Final

• What are the major functions of the kidney?

  filtration, regulation of fluid balance, electrolyte balance, acid-base balance, blood pressure regulation, red blood cell production
• What are the differences between the cortex and the medulla in terms of structures?

  Cortex: Outer layer. Medulla: Inner region.

  ~ so think of the cortex as where the filtering happens, and the medulla where the pee is collected
• What are the differences between the cortex and the medulla in terms of osmotic concentrations?

  medulla is saltier (higher osmotic concentration) than the cortex
• What are the differences between the cortex and the medulla in terms of function?

  cortex is the filter and medulla is the concentrator
• Why is blood flow to the kidney a priority?

  Filtration.

  basically to keep the body balanced and healthy
• What are the opposing pressures in glomerular filtration?

  Hydrostatic pressure and osmotic pressure.
• Hydrostatic Pressure is the pushing force that pushes fluid and small molecules out of the blood vessels into the kidney's filtering system
• Osmotic pressure is the pulling force that tries to draw fluid and molecules back into the blood vessels from the kidney's filtering system
• What is the functional unit of the kidney?

  Nephron
• What are the blood vessels associated with the nephron?

  Afferent Arteriole, Glomerulus, Efferent Arteriole, Peritubular Capillaries (Vasa Recta)
• What are the general regions of the nephron?

  Renal corpuscle, proximal convoluted tubule, loop of Henle, distal convoluted tubule, collecting duct.
• What happens in the renal corpuscle?

  this is where blood filtration happens
• What happens in the proximal tubule?

  reabsorption of minerals and water, secretion of wastes

  
  

  think of it as a busy highway where the body decides what to keep and what to get rid of from the filtrate.
• What happens in the loop of henle?

  concentrates urine and reabsorbs water

  
  

  Think of it like a water recycling system that helps the body conserve water by making urine more concentrated.
• What happens in the distal tubules?

  Fine-tuning of minerals and pH regulation

  
  

  Think of it as the last stop for adjusting the body's chemical balance before urine is formed.
• What happens in the collecting duct?

  final concentration and balances salt

  
  

  Think of it as the last checkpoint where the body decides how much water to keep and how concentrated the urine should be before it's sent out of the body.
• Where does most of the reabsorption take place?

  Proximal tubule
• The major function of nephron is reabsorption
• How is glomerular filtration rate controlled at the afferent arteriole?

  by adjusting the diameter of the arteriole
• What things are reabsorbed in the proximal tubuleand their mechanisms of absorption?

  Glucose and Amino Acids: active transport

  Sodium: active transport

  Water: passive diffusion and osmosis

  Chloride: passive diffusion

  Bicarbonate: active transport and passive diffusion
• What substances are secreted into the tubule?

  H+, K+, Ammonia (NH3), Creatinine, drugs and toxins
• What happens in loop of Henle in the descending and ascending limbs?

  descending limb: removes water and concentrates the filtrate

  ascending limb: removes salt and dilutes the filtrate
• How does the loop of Henle concentrate the medullary interstitium?

  through a process of salt accumulation

  descending limb: water leaves through osmosis, therefore the remains filtrate becomes saltier

  ascending limb: salt is actively pumped out into surrounding tissue which makes the tissue saltier
• What are the osmolarities of the filtrate going into and coming out of the loop of Henle?

  Input: 300 milliosmoles

  Output: lower

  osmolarity decreases as it moves through the loop of Henle
• How do the vasa recta remove mostly water and not all the other solutes?

  because of the way they are structured and the way the interact with their surrounding tissue

  Permeability and counter current exchange
• What is the urea cycle and how does it work?

  the urea cycle is how your body gets rid of nitrogen
• How does the urea cycle work?


  forms urea (liver takes ammonia and combines it with CO2)

  transports to kidneys

  excretion in Urine
• How does ADH affect aquaporin presence in collecting duct?

  More ADH means the body wants to keep water so it inserts more aquaporins to reabsorb

  Less ADH means the body wants to get rid of water so fewer aquaporins are inserted which lets more water pass through to be released in the urine
• How does ADH affect urine volume?

  high ADH= less urine volume

  low ADH= more urine volume
• what is secreted in the distal convoluted tubule?

  K+, H+, NH4+, drugs and toxins
• what is reabsorbed in the distal convoluted tubule?

  Calcium ions, sodium ions, water, chloride ions
• What actions do aldosterone and ANF have in the distal tubule?

  Aldosterone: keeps sodium and water in the body

  ANF: gets rid of them
• What is the juxtaglomerular apparatus?

  control center that monitors blood pressure and sodium levels to help keep the body's balance in check
• What triggers renin to be released?

  Low blood pressure or a decrease in sodium levels in the kidneys
• How does the renin-angiotensin system work?

  1. low blood pressure or low sodium triggers the release of renin
  2. renin turns a protein into angiotensin I
  3. gets converted to angiotensin II
  4. raises blood pressure
• What is the net effect on blood pressure?

  to raise blood pressure
• Why would giving someone an ACE inhibitor to treat high bloodpressure?

  Ace inhibitors help lower blood pressure by relaxing blood vessels and reducing fluid retention
• What are the basic processes of the digestive tract?

  eating, breaking down, chemical action, absorption, moving along, gets rid of waste
• What are the features in the mucosa?

  epithelium: thin layer that covers the surface that helps with absorption and secretion

  lamina propria: connective tissue that supports the epithelium

  muscularis mucosae: smooth layer that helps move mucous and helps with digestion
• What are the features in the submucosa?

  blood vessels, nerves, glands