Kidneys Anatomy and Structure
43 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the typical length of a kidney?

  • 10 cm (correct)
  • 8 cm
  • 6 cm
  • 12 cm
  • Which structure collects urine from the kidney's calices?

  • Renal artery
  • Renal hilum
  • Renal pelvis (correct)
  • Ureter
  • Where are the kidneys located in relation to the vertebral levels?

  • T8 - T11
  • L1 - L4
  • T10 - L2
  • T12 - L3 (correct)
  • What is the main role of perirenal fat?

    <p>Cushions and insulates kidneys (A)</p> Signup and view all the answers

    Which option describes the structure that opens into the renal sinus?

    <p>Renal pelvis (B)</p> Signup and view all the answers

    Which organ partially covers the right kidney?

    <p>Liver (B)</p> Signup and view all the answers

    What percentage of circulating blood goes through the kidneys?

    <p>10% (C)</p> Signup and view all the answers

    Which surface of the kidney contains the renal hilum?

    <p>Medial (concave) surface (A)</p> Signup and view all the answers

    What is the primary function of the proximal convoluted tubules?

    <p>Absorption of nutrients and ions from the filtrate (B)</p> Signup and view all the answers

    How do juxtaglomerular apparatus cells contribute to blood pressure regulation?

    <p>By detecting changes in sodium concentration (B)</p> Signup and view all the answers

    Which segment of the nephron is primarily responsible for the reabsorption of water and salts?

    <p>Loop of Henle (A)</p> Signup and view all the answers

    What type of epithelium is found in the descending limb of the Loop of Henle?

    <p>Simple squamous epithelium (B)</p> Signup and view all the answers

    Which hormone acts on principal cells in the distal convoluted tubules to increase water reabsorption?

    <p>Antidiuretic hormone (ADH) (D)</p> Signup and view all the answers

    What process occurs primarily in the renal tubules after glomerular filtration?

    <p>Tubular reabsorption of water and solutes (B)</p> Signup and view all the answers

    What structure collects filtered urine from several nephrons?

    <p>Collecting duct (B)</p> Signup and view all the answers

    Which part of the nephron features microvilli to enhance absorption capabilities?

    <p>Proximal convoluted tubules (C)</p> Signup and view all the answers

    What kind of epithelium lines the thick ascending limb of the Loop of Henle?

    <p>Simple cuboidal and low columnar epithelium (A)</p> Signup and view all the answers

    What is the main purpose of the papillary ducts in the renal system?

    <p>To transport urine to the minor calyces (B)</p> Signup and view all the answers

    What is the primary function of the glomerular capillaries?

    <p>Filtration of blood (A)</p> Signup and view all the answers

    Which structure allows for the prevention of retrograde movement of urine back to the kidney?

    <p>Ureter (D)</p> Signup and view all the answers

    Where do interlobular arterioles predominantly found?

    <p>Cortex (A)</p> Signup and view all the answers

    What are the final venous structures that combine to form the renal vein?

    <p>Interlobar, arcuate, and interlobular veins (B)</p> Signup and view all the answers

    What is the primary force that promotes glomerular filtration?

    <p>Blood hydrostatic pressure (C)</p> Signup and view all the answers

    Which type of epithelium is found lining the urinary bladder?

    <p>Transitional epithelium (D)</p> Signup and view all the answers

    Which arteries pass between the renal pyramids towards the cortex?

    <p>Lobar arteries (B)</p> Signup and view all the answers

    Which range accurately represents normal values for glomerular filtration rate (GFR) in males?

    <p>125-150 ml/min (B)</p> Signup and view all the answers

    From which major artery do renal arteries arise?

    <p>Abdominal aorta (B)</p> Signup and view all the answers

    How does renal autoregulation maintain GFR during fluctuations in blood pressure?

    <p>By causing afferent arterioles to constrict in response to increased blood pressure (D)</p> Signup and view all the answers

    Which hormone is released from the atria of the heart and increases GFR?

    <p>Atrial natriuretic peptide (ANP) (B)</p> Signup and view all the answers

    What structure do efferent arterioles drain into after the glomerulus?

    <p>Peritubular capillaries (B)</p> Signup and view all the answers

    What is a primary site of potential obstruction within the ureter?

    <p>Both A and B (D)</p> Signup and view all the answers

    Which of the following substances is NOT typically reabsorbed by the renal tubules?

    <p>Urea (A)</p> Signup and view all the answers

    What is the usual net filtration pressure (NFP) in the glomerulus?

    <p>10 mmHg (A)</p> Signup and view all the answers

    How do arcuate arteries relate to interlobular arterioles?

    <p>They give rise to interlobular arterioles (C)</p> Signup and view all the answers

    What effect does sympathetic stimulation have on renal blood flow?

    <p>It decreases renal blood flow (A)</p> Signup and view all the answers

    Which ion is NOT reabsorbed in the renal tubules?

    <p>Calcium (Ca2+) (D)</p> Signup and view all the answers

    What happens to glomerular filtration if the glomerular blood hydrostatic pressure falls below 45 mmHg?

    <p>Filtration ceases (B)</p> Signup and view all the answers

    What is the approximate amount of urine eliminated per day under normal circumstances?

    <p>1-2 liters (D)</p> Signup and view all the answers

    What percentage of water is reabsorbed in the proximal convoluted tubules?

    <p>65% (D)</p> Signup and view all the answers

    Which mechanism is primarily responsible for the reabsorption of small molecules such as glucose and amino acids in the proximal convoluted tubules?

    <p>Pinocytosis (B)</p> Signup and view all the answers

    In the loop of Henle, where does the majority of water reabsorption occur?

    <p>Descending limb (B)</p> Signup and view all the answers

    What ions are primarily secreted from the renal tubules to help regulate blood pH?

    <p>Hydrogen and Ammonium (C)</p> Signup and view all the answers

    Which structure contributes to urine concentration based on the presence of Antidiuretic Hormone (ADH)?

    <p>Collecting duct (C)</p> Signup and view all the answers

    Flashcards

    Location of Kidneys

    Kidneys are paired organs situated retroperitoneally in the upper part of the abdominal cavity, attached to the posterior abdominal wall, generally corresponding to the T12-L3 vertebral level.

    Kidney Size

    Kidneys are roughly 10 cm (length) x 5 cm (width) x 2.5 cm (thickness).

    Renal Hilum

    The indented area on the medial surface of the kidney where the renal artery, renal vein, and renal pelvis enter and exit.

    Renal Sinus

    A large internal space or cavity within the kidney, containing the renal pelvis and structures associated with urine collection.

    Signup and view all the flashcards

    Renal Pelvis

    A funnel-shaped structure in the kidney that collects urine from the calyces. It is the proximal dilation of the ureter.

    Signup and view all the flashcards

    Renal Cortex

    The outer layer of the kidney.

    Signup and view all the flashcards

    Renal Medulla

    The inner layer of the kidney, containing renal pyramids.

    Signup and view all the flashcards

    Kidney Blood Supply

    Approximately 10% of the circulating blood flows through the kidneys.

    Signup and view all the flashcards

    Proximal convoluted tubule location

    Located in the cortex of the kidney.

    Signup and view all the flashcards

    Loop of Henle location

    Located in the medulla of the kidney.

    Signup and view all the flashcards

    Distal convoluted tubule location

    Located in the cortex of the kidney.

    Signup and view all the flashcards

    Glomerular capsule layers

    Visceral layer (podocytes) and parietal layer (simple squamous epithelium).

    Signup and view all the flashcards

    Proximal convoluted tubule cells

    Simple cuboidal cells with microvilli for increased absorption and secretion.

    Signup and view all the flashcards

    Loop of Henle parts

    Descending and ascending limbs, including thin and thick segments in juxtamedullary nephrons.

    Signup and view all the flashcards

    Juxtaglomerular apparatus (JGA)

    Structure regulating blood pressure in the kidneys, formed by macula densa and afferent arteriole.

    Signup and view all the flashcards

    Principal cells

    Cells in distal convoluted tubules responding to hormones ADH and aldosterone.

    Signup and view all the flashcards

    Tubular Reabsorption

    Process of reclaiming useful substances from the filtrate.

    Signup and view all the flashcards

    Collecting Duct

    Where distal convoluted tubules empty into, directing urine formation.

    Signup and view all the flashcards

    What is glomerular filtration?

    The process where blood is filtered in the glomerulus, separating water and small solutes from blood cells and large proteins.

    Signup and view all the flashcards

    What is the filtration rate in glomerular filtration?

    The rate at which filtrate is produced in all nephrons per minute, approximately 125 ml/min for males and 105 ml/min for females.

    Signup and view all the flashcards

    What is the net filtration pressure (NFP)?

    The pressure difference that drives filtration in the glomerulus, calculated as the glomerular blood hydrostatic pressure minus the capsular hydrostatic pressure and blood colloid osmotic pressure.

    Signup and view all the flashcards

    What is renal autoregulation?

    The ability of the kidneys to adjust blood flow and GFR in response to blood pressure changes.

    Signup and view all the flashcards

    How does myogenic mechanism work?

    Increased blood pressure stretches the afferent arterioles, causing vasoconstriction which reduces blood flow and maintains GFR.

    Signup and view all the flashcards

    What is the role of the sympathetic nervous system in GFR regulation?

    Sympathetic stimulation restricts blood flow to the kidneys by vasoconstriction, preserving blood volume and diverting blood to other organs.

    Signup and view all the flashcards

    What is the effect of Angiotensin II on GFR?

    Angiotensin II reduces GFR by constricting the efferent arteriole, thereby decreasing blood flow through the glomerulus.

    Signup and view all the flashcards

    What is the effect of Atrial Natriuretic Peptide (ANP) on GFR?

    ANP, released from the heart when blood volume increases, increases GFR by promoting vasodilation of afferent arterioles and reducing the reabsorption of sodium and water.

    Signup and view all the flashcards

    What is tubular reabsorption?

    The process of moving essential substances from the filtrate back into the bloodstream.

    Signup and view all the flashcards

    What is tubular secretion?

    The process of transporting wastes and excess substances from the blood into the filtrate for excretion.

    Signup and view all the flashcards

    Renal arteries

    Blood vessels that directly branch from the abdominal aorta and supply blood to the kidneys. They enter the kidney through the hilum.

    Signup and view all the flashcards

    Lobar arteries

    Found within the kidney, these arteries branch from the renal arteries and carry blood towards the cortex between renal pyramids.

    Signup and view all the flashcards

    Arcuate arteries

    These arteries curve between the cortex and medulla within the kidney, supplying blood to these regions.

    Signup and view all the flashcards

    Interlobular arterioles

    Smallest branches of the arcuate arteries, found within the cortex of the kidney, supplying blood to the nephrons.

    Signup and view all the flashcards

    Afferent arteriole

    A specialized arteriole that branches from the interlobular arteriole and carries blood to the glomerulus for filtration.

    Signup and view all the flashcards

    Glomerular capillaries

    Specialized capillaries within the glomerulus where blood filtration takes place, forming the filtrate.

    Signup and view all the flashcards

    Efferent arteriole

    Arteriole that carries blood away from the glomerulus after filtration, leading to peritubular capillaries for reabsorption.

    Signup and view all the flashcards

    Peritubular capillaries

    Capillaries surrounding the tubules of the nephron, responsible for reabsorbing essential nutrients and water back into the blood.

    Signup and view all the flashcards

    Proximal Convoluted Tubule (PCT) Reabsorption

    The PCT is where most of the reabsorption of water, electrolytes, nutrients, and other substances occurs, returning them to the bloodstream. Important examples include 65% water reabsorption via osmosis, 65% Na and K ions, 100% glucose and amino acids, and 50% urea.

    Signup and view all the flashcards

    Interlobular veins

    Veins within the kidney's cortex, collecting blood from the peritubular capillaries.

    Signup and view all the flashcards

    Ureters

    Muscular tubes that transport urine from the renal pelvis to the urinary bladder.

    Signup and view all the flashcards

    Loop of Henle Reabsorption

    The loop of Henle further reabsorbs water and solutes, playing a crucial role in concentrating urine. The descending limb reabsorbs mostly water, while the ascending limb reabsorbs Na, K, and Cl. Notably, water reabsorption is minimal in the ascending limb.

    Signup and view all the flashcards

    Distal Convoluted Tubule (DCT) Reabsorption

    The DCT fine-tunes urine composition by reabsorbing remaining water, sodium, chloride, and variable amounts of calcium. Parathyroid hormone stimulates calcium reabsorption.

    Signup and view all the flashcards

    Principal Cells Reabsorption

    Located in the late DCT and collecting duct, principal cells reabsorb water, sodium, and variable amounts of urea. They are also responsible for potassium secretion.

    Signup and view all the flashcards

    Intercalated Cells in DCT and Collecting Duct

    These cells contribute to acid-base balance by reabsorbing bicarbonate and secreting hydrogen ions, playing a crucial role in maintaining pH.

    Signup and view all the flashcards

    Study Notes

    Kidneys

    • Paired organs located retroperitoneally in the upper abdominal cavity, corresponding to vertebral levels T12-L3.
    • Ribs 11 and 12 partially cover the upper poles.
    • The right kidney is slightly lower than the left due to the liver's size.
    • 10 cm long, 5 cm wide, and 2.5 cm thick.
    • Surrounded by perirenal fat, which insulates and minimizes kidney mobility.
    • Perirenal fat extends into the renal sinus.

    External Anatomy of Kidneys

    • Superior pole (where the adrenal gland is found).
    • Inferior pole.
    • Lateral (convex) surface.
    • Medial (concave) surface with the renal hilum (renal artery, renal vein, and renal pelvis).
    • Renal pelvis, a urine-collecting structure, is formed from the fusion of minor calices (at tips of renal pyramids) which then blend into major calices to form the renal pelvis.
    • The renal hilum opens into a large space called the renal sinus.

    Structure of Kidneys

    • External surface covered by a renal capsule.
    • On Cross-section, the cortex is situated peripherally.
    • The medulla is centrally situated, divided into renal pyramids by renal columns.

    Vascular Supply of Kidneys

    • Renal arteries branch directly from the abdominal aorta (at L2 level.)
    • Within the hilum and renal pelvis they divide into:
      • 2 or 3 lobar arteries that run between renal pyramids, towards the cortex.
      • Arcuate arteries run between the cortex and medulla.
      • Interlobular arterioles, which further divide into afferent arterioles, then glomerular capillaries, efferent arterioles, then peritubular capillaries.
    • Peritubular capillaries lead to interlobular veins, which then become arcuate, interlobar veins, and unite to form the renal vein.
    • Renal veins drain into the inferior vena cava.

    Ureters

    • Muscular tubes (25-30 cm long) extending from the renal pelvis to the urinary bladder.
    • Three constricted areas for potential obstruction:
      • Junction with renal pelvis.
      • Crossing the pelvic inlet.
      • Piercing the bladder wall.

    Urinary Bladder (Vesica Urinaria)

    • Located within the true pelvis, posterior to the pubic symphysis in adults.
    • Lined with transitional epithelium.
    • The wall is mostly composed of the detrussor muscle, which converges at the bladder neck to form the sphincter.
    • Trigone area where ureteric openings on opposing sides are present.

    Nephron

    • Basic functional unit of the kidney.
    • 80-85% located in the renal cortex.
    • Shorter loops of Henle in most nephrons.
    • Juxtamedullary nephrons (15-20%) are closer to the renal medulla with longer loops of Henle.

    Histology of Nephron and Collecting Duct

    • Glomerular capsule is composed of visceral (podocytes) and parietal (simple squamous epithelium) layers, separated by capsular/Bowman space.

    Renal Physiology

    • Three processes:
      • Glomerular filtration (primary filtering process).
      • Tubular reabsorption.
      • Tubular secretion (removing substances from the blood).
    • Glomerular Filtration Rate (GFR) is approximately 125 ml/minute in males and 105 ml/minute in females.

    Regulation of GFR

    • Renal autoregulation (myogenic and tubuloglomerular feedback)
    • Neural regulation (sympathetic stimulation)
    • Hormonal regulation (Renin-Angiotensin, ADH, ANP).

    Tubular Reabsorption

    • Reabsorption of water, glucose, amino acids, ions (Na+, Cl-, K+, HCO3–, HPO4-), and urea.

    Tubular Secretion

    • Removing substances from the blood into the tubule. Examples include H+, K+, NH4+, creatinine, and drugs.

    Loop of Henle

    • Reabsorption and secretion processes occur within the ascending and descending limbs.

    Distal Convoluted Tubules

    • Reabsorption of water, sodium, and chloride.
    • Active secretion of ions, such as potassium and hydrogen.

    Principal and Intercalated Cells of Late DCT and Collecting Duct

    • Principal cells reabsorb sodium and secrete potassium.
    • Intercalated cells regulate acid-base balance by active secretion of hydrogen ions, and reabsorption of bicarbonate ions.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Urinary System Handout PDF

    Description

    This quiz explores the anatomy and structure of the kidneys, including their location, external features, and internal organization. Test your knowledge on the renal anatomy, including the renal hilum, pelvis, and the surrounding structures. Perfect for students learning about human anatomy.

    More Like This

    Kidney Anatomy and Position
    31 questions
    The Kidney Anatomy
    21 questions

    The Kidney Anatomy

    StylishOmaha1982 avatar
    StylishOmaha1982
    Kidney Anatomy Quiz
    10 questions

    Kidney Anatomy Quiz

    FriendlyBernoulli9626 avatar
    FriendlyBernoulli9626
    Kidney Anatomy and Structure
    24 questions
    Use Quizgecko on...
    Browser
    Browser