Urinary System Not Narrated

Page 1: Urinary System Overview

  • Introduction to Chapter 24 of Human Anatomy

  • Focus on the structure and function of the urinary system.

Page 2: Objectives

  • Identify the gross anatomy of the urinary system:

    • Kidneys

    • Ureters

    • Urinary Bladder

    • Urethra

  • Understand the microscopic anatomy of the urinary system, including nephron structures.

  • Describe blood flow to and from the kidneys through renal blood vessels and glomeruli.

  • Explain urine production mechanisms.

  • Define micturition and describe its neural control.

  • Discuss the kidneys' role in blood pressure regulation.

Page 3: Organs of the Urinary System

  • Urinary organs include:

  • Kidneys

  • Ureters (right and left)

  • Urinary bladder

  • Urethra

Page 4: Overall Functions of the Urinary System

  • Key functions:

  • Removal of organic waste from body fluids

  • Discharge of waste products into the environment

  • Maintenance of homeostasis of blood plasma volume and solute concentration

Page 5: Other Homeostatic Functions of the Urinary System

  • Regulation of:

  • Water and electrolyte balance

  • Metabolic waste and foreign chemical excretion

  • Body fluid osmolality and electrolyte concentrations

  • Acid-base balance

  • Secretion and metabolism of hormones

  • Gluconeogenesis

  • Activation of vitamin D

  • Production of renin (blood pressure regulation) and erythropoietin (RBC production)

Page 6: Kidneys Location

  • Kidneys are located in the posterior abdominal cavity

  • Positioned from the 11th/12th thoracic vertebra to about the 3rd lumbar vertebra

  • Right kidney slightly lower due to liver presence

  • Size: Approximately 3cm x 6cm x 12cm

Page 7: Urinary Bladder and Ureters

  • Urinary bladder: temporary storage for urine

  • Paired ureters transport urine from kidneys to the bladder

  • Urethra: transports urine from the bladder out of the body

Page 8: Abdominal Structures

  • Overview of anatomical relations in the abdominal region, including:

  • Adrenal gland

  • Aorta

  • Inferior vena cava

  • Various arteries and veins, including right renal and common iliac structures

Page 9: External Structures of the Kidney

  • Three protective layers:

  • Renal capsule: fibrous, preventing infections

  • Adipose capsule: fatty layer for cushioning and attachment

  • Renal fascia: outer layer that anchors the kidney

  • Importance of layers in protecting the kidneys

Page 10: Internal Anatomy of Kidneys

  • Inner structures divided into:

  • Renal cortex

  • Renal medulla (contains renal pyramids and columns)

  • Renal pelvis: funnel-shaped tube for urin flow to ureter

  • Urine drains from renal pyramids through calices into the pelvis

Page 11: Internal Kidney Structures

  • Diagram/overview of kidney anatomy including major features such as:

  • Renal cortex

  • Medulla

  • Renal pelvis and associated blood vessels

Page 12: Internal Gross Anatomy

  • Detailed description of kidney structures including:

  • Renal cortex, medulla, minor and major calyx, renal pelvis, hilum

  • Importance of each structure in kidney function and urine production

Page 13: Blood Vessels of the Kidney

  • Overview of renal blood vessel architecture, including:

  • Renal artery, interlobar arteries, arcuate arteries, cortical radiate arteries

  • Venous drainage via corresponding veins back to the inferior vena cava

Page 14: Nephron Blood Vessels

  • Nephron association with two capillary beds:

  • Glomeruli

  • Peritubular capillaries or vasa recta

Page 15: Glomerulus

  • Functions:

  • Produces filtrate that forms urine

  • Structural features: afferent and efferent arterioles

  • Generates 1 liter of fluid every 8 minutes

Page 16: Peritubular Capillaries

  • Specialized for absorption, low-pressure, and porous

  • Essential for secretion processes in urine formation

Page 17: Nerve Supply to Kidneys

  • Innervation by renal plexus, influenced by sympathetic fibers

Page 18: Microscopic Anatomy of Kidneys

  • Overview of nephron structures, including renal corpuscle and renal tubule parts

Page 19: Histology of the Nephron

  • Microscopic view of nephron anatomy including types of cells and their functions

Page 20: Nephron Anatomy

  • Composed of:

  • Renal corpuscle

  • Renal tubule (including proximal and distal convoluted tubule, and nephron loop)

  • Collecting ducts are separate from nephrons

Page 21: Nephron Types

  • Comparison of nephron types:

  • Cortical nephrons: shorter loops, more abundant

  • Juxtamedullary nephrons: longer loops, important for urine concentration

Page 22: Nephron Models

  • Visual aid showing the arrangement and blood vessel connections associated with nephron types

Page 23: Renal Corpuscle Anatomy

  • Details of the renal corpuscle, including various components like Bowman’s capsule and capillaries

Page 24: Renal Corpuscle Structure

  • Components: glomerular capsule and glomerulus

Page 25: The Filtration Membrane

  • Composed of:

  • Endothelial layer (fenestrated)

  • Podocytes and their foot processes creating filtration slits

  • Basement membrane functions to block larger molecules

Page 26: The Renal Tubule

  • Sequence and function of renal tubule segments:

  • Proximal convoluted tubule (PCT)

  • Nephron loop

  • Distal convoluted tubule (DCT)

  • Collecting duct as the final segment (not part of nephron)

Page 27: Collecting Ducts

  • Function: receive urine from multiple nephrons, play a role in fluid conservation via ADH influence

Page 28: Urine Formation Processes

  • Three main processes involved:

  • Glomerular filtration

  • Tubular reabsorption

  • Tubular secretion

  • Urine formation aims for waste elimination and homeostasis

Page 29: Fluid Flow to Excretion

  • Pathway of filtrate: glomerular capsule → PCT → nephron loop → DCT → collecting duct → papillary duct → calyxes → renal pelvis → ureter → bladder → urethra

Page 30: Juxtaglomerular Complex

  • Location: where distal tubule contacts arterioles

  • Role in blood pressure regulation via juxtaglomerular cells that secrete renin

Page 31: Juxtaglomerular Apparatus (JGA)

  • Macula densa role as osmoreceptors to regulate renin secretion

Page 32: Ureters

  • Structure: transitional epithelium mucosa, muscularis, and adventitia

  • Function to carry urine to the bladder

  • Ureters' entry into the bladder prevents backflow

Page 33: Urinary Bladder Function

  • Structure: collapsible muscular sac that stores urine

  • Full bladder expands into abdominal cavity; empty will stay within the pelvis

Page 34: Urinary Bladder Layers

  • Composition:

  • Mucosa: transitional epithelium

  • Thick muscular layer (detrusor muscle)

  • Adventitia (fibrous layer)

Page 35: Urethra Structure

  • Epithelium varies:

  • Transitional and stratified squamous

  • Involuntary and voluntary sphincters control urine flow

Page 36: Positioning of the Urinary Bladder

  • Anatomical reference points and positioning of bladder in males vs females

Page 37: Female Reproductive Organs

  • Overview of the anatomical arrangement for the female pelvis including urinary structures

Page 38: Male Reproductive Organs

  • Similar anatomical overview but tailored for the male gender

Page 39: Micturition

  • The process of bladder emptying initiated by distension; involves spinal reflexes affecting sphincters and muscle contractions

Page 40: Disorders of the Urinary System

  • Common disorders and their symptoms:

  • Urinary tract infections (more common in women)

  • Renal calculi (kidney stones)

  • Bladder cancer (more prevalent in men)

  • Kidney cancer (arising from nephron cells)