🎧 New: AI-Generated Podcasts Turn your study notes into engaging audio conversations. Learn more

Nephron Physiology Quiz
42 Questions
0 Views

Nephron Physiology Quiz

Created by
@EasedVerism

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of the glomerulus in a nephron?

  • Filtration of a protein-free plasma into the tubular component (correct)
  • Reabsorption of sodium and water
  • Exchanges with the fluid in the tubular lumen
  • Production of substances involved in kidney function control
  • What percentage of reabsorption occurs in the Proximal Convoluted Tubule (PCT)?

  • 50%
  • 25%
  • 80%
  • 65% (correct)
  • What is the main function of the Loop of Henle?

  • Establishing an osmotic gradient in the renal medulla (correct)
  • Reabsorption of sodium and water
  • Filtration of a protein-free plasma into the tubular component
  • Production of substances involved in kidney function control
  • What is the function of the Peritubular capillaries?

    <p>Supply the renal tissue; involved in exchanges with the fluid in the tubular lumen</p> Signup and view all the answers

    What is the function of the Afferent arteriole?

    <p>Carries blood to the glomerulus</p> Signup and view all the answers

    What is the function of the Distal tubule and Collecting duct?

    <p>Variable, controlled reabsorption of Na+ and H2O and secretion of K+ and H+</p> Signup and view all the answers

    What is the location of Cortical nephrons?

    <p>Entirely in the cortex</p> Signup and view all the answers

    What is the net glomerular filtration pressure?

    <p>+10mmHg</p> Signup and view all the answers

    What is the function of the Juxtaglomerular apparatus?

    <p>Produces substances involved in the control of kidney function</p> Signup and view all the answers

    What is the normal daily average glomerular filtration rate (GFR) in mL/min?

    <p>115-125</p> Signup and view all the answers

    Which of the following factors decreases the glomerular filtration rate (GFR)?

    <p>Sympathetic stimulation</p> Signup and view all the answers

    What is the main factor that determines the rate of glomerular filtration?

    <p>Both net filtration pressure and properties of the glomerular membrane</p> Signup and view all the answers

    What is the hydrostatic pressure in Bowman's capsule?

    <p>15mmHg</p> Signup and view all the answers

    Which of the following is NOT a factor that decreases the glomerular filtration rate (GFR)?

    <p>Parasympathetic stimulation</p> Signup and view all the answers

    What is the primary function of glomerular filtration?

    <p>To separate large proteins and cells from small substances</p> Signup and view all the answers

    What is the main driving force behind glomerular filtration?

    <p>The glomerular capillary blood pressure</p> Signup and view all the answers

    What is the purpose of the tubular reabsorption process?

    <p>To selectively return valuable substances to the blood</p> Signup and view all the answers

    What is the function of the podocyte cells in the glomerular membrane?

    <p>To form the filtration slits</p> Signup and view all the answers

    What is the result of glomerular filtration?

    <p>Water, ions, and small molecules enter the nephron tubules</p> Signup and view all the answers

    What is the name of the structure where the filtrate enters the nephron tubules?

    <p>Bowman's capsule</p> Signup and view all the answers

    What is the function of the basement membrane in the glomerular membrane?

    <p>To act as a gelatinous layer</p> Signup and view all the answers

    What is the value of the glomerular capillary blood pressure?

    <p>55mmHg</p> Signup and view all the answers

    What is the function of the ureters?

    <p>To transport urine from the kidney to the bladder</p> Signup and view all the answers

    What is the trigone of the urinary bladder?

    <p>Three openings in the bladder</p> Signup and view all the answers

    What affects the glomerular filtration rate (GFR) through changes in plasma protein concentration?

    <p>Pop</p> Signup and view all the answers

    What is the function of antidiuretic hormone (ADH)?

    <p>To prevent excessive water loss in urine</p> Signup and view all the answers

    What is the primary mechanism that maintains constant GFR despite changes in mean systemic arterial blood pressure (MAP)?

    <p>Autoregulation</p> Signup and view all the answers

    What is the normal pH range for blood?

    <p>7.35 to 7.45</p> Signup and view all the answers

    What is the result of increased Pglom on the afferent arteriole?

    <p>Vasoconstriction</p> Signup and view all the answers

    What is the function of the bicarbonate buffer system?

    <p>To maintain blood pH by reacting to changes in hydrogen ion concentration</p> Signup and view all the answers

    What is the role of the macula densa in tubuloglomerular feedback?

    <p>Releases ATP and adenosine to cause afferent arteriole vasoconstriction</p> Signup and view all the answers

    How does the respiratory system control acid-base balance?

    <p>By converting carbon dioxide to bicarbonate ion and transporting it in the plasma</p> Signup and view all the answers

    What is the effect of sympathetic nervous system stimulation on GFR?

    <p>Decreases GFR</p> Signup and view all the answers

    What is the function of the internal urethral sphincter?

    <p>To involuntarily release urine from the body</p> Signup and view all the answers

    What is the primary function of tubular reabsorption?

    <p>To return needed substances from the glomerular filtrate back to the blood</p> Signup and view all the answers

    Why are urinary infections more common in women than men?

    <p>Because the urethra is shorter in women</p> Signup and view all the answers

    What percentage of water is reabsorbed in the proximal convoluted tubule (PCT)?

    <p>8%</p> Signup and view all the answers

    What is the function of the detrusor muscle?

    <p>To contract and relax the bladder wall to facilitate urine storage</p> Signup and view all the answers

    At what age does the control of the voluntary urethral sphincter start?

    <p>At 18 months</p> Signup and view all the answers

    What is the role of vasopressin (ADH) in regulating water reabsorption?

    <p>Inserts aquaporins into the DCT and Collecting Duct to increase water reabsorption</p> Signup and view all the answers

    What is the normal pH of urine due to H+ secretion?

    <p>6</p> Signup and view all the answers

    What happens when two drugs that use the same carrier for elimination are taken together?

    <p>Neither drug is fully eliminated</p> Signup and view all the answers

    Study Notes

    Nephron Physiology

    • A nephron is the functional unit of the kidney, containing specialized blood vessels and tubules that regulate the exchange of materials between the blood and the body.
    • The nephron consists of:
      • Afferent arteriole: carries blood to the glomerulus
      • Glomerulus: a tuft of capillaries that filters a protein-free plasma into the tubular component
      • Efferent arteriole: carries blood from the glomerulus
      • Peritubular capillaries: supply the renal tissue and are involved in exchanges with the fluid in the tubular lumen
      • Proximal convoluted tubule (PCT): uncontrolled reabsorption and secretion of selected substances occur here
      • Loop of Henle: establishes an osmotic gradient in the renal medulla that is important for producing urine of varying concentration
      • Distal convoluted tubule (DCT) and collecting duct: variable, controlled reabsorption of Na+ and H2O and secretion of K+ and H+ occur here

    Types of Nephrons

    • Cortical nephrons: located entirely in the cortex, account for most nephrons
    • Juxtamedullary nephrons: found at the boundary of the cortex and medulla

    Nephron Processes

    • 3 main processes in the nephron:
      1. Glomerular filtration: separation of cells and large proteins from plasma
      2. Tubular reabsorption: valuable substances are selectively returned to the blood
      3. Tubular secretion: unneeded substances are selectively removed from the blood and added to the nephron

    Glomerular Filtration

    • Glomerular filtration is the nonspecific separation of large substances (cells, proteins) from small substances (water, ions, small molecules)
    • Blood enters at the afferent arteriole, passes through the glomerular membrane, and exits at the efferent arteriole
    • The glomerular membrane consists of:
      • Glomerular capillary wall: simple squamous epithelium with large pores (fenestrations)
      • Basement membrane: collagen and glycoprotein gelatinous layer
      • Capsular filtration slits: podocyte cells with processes link together to form filtration slits

    Glomerular Filtration Pressure

    • Glomerular filtration pressure is regulated by various pressures at the glomerular membrane:
      • Pglom (glomerular capillary blood pressure): 55 mmHg
      • Pop (plasma-colloid osmotic pressure): 30 mmHg
      • PBC (Bowman's capsule hydrostatic pressure): 15 mmHg
    • Net glomerular filtration pressure: +10 mmHg

    Glomerular Filtration Rate (GFR)

    • GFR is the rate of glomerular filtration and is important for assessing kidney health and disease
    • Factors affecting GFR:
      • Net filtration pressure (Pglom, Pop, PBC)
      • Properties of the glomerular membrane (pore size, filtration slit size)
    • GFR can be altered by:
      • Plasma protein concentration (affects Pop)
      • Hydration level (affects Pglom and PBC)
      • Urinary tract obstruction (PBC)
      • Mean arterial blood pressure (MAP affects Pglom)

    GFR Regulation

    • Autoregulation: the main way kidneys maintain a constant GFR as MAP changes
      • Myogenic mechanism: afferent arteriole constricts or dilates in response to changes in MAP
      • Tubuloglomerular feedback: macula densa senses changes in GFR and releases ATP and adenosine to constrict or dilate the afferent arteriole
    • Sympathetic nervous system stimulation decreases GFR to decrease urine volume and retain fluids

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    urinary system.pdf

    Description

    Test your knowledge on nephron structure and function, including renal corpuscle, glomerulus, and tubules.

    More Quizzes Like This

    Renal Blood Supply Pathway Quiz
    155 questions
    Nefron Structure and Function
    10 questions
    Use Quizgecko on...
    Browser
    Browser