A detailed medical educational flashcard poster titled "RENAL CLEARANCE TESTS" in large bold white text on a dark navy blue banner at the top, similar style to a RAAS medical diagram. Layout: white background, colorful numbered sections with icons and diagrams, professional medical textbook style. Top banner: Dark navy blue with "RENAL CLEARANCE TESTS" in large bold white text. Below it a light yellow box with text: "Renal Clearance = Volume of plasma completely cleared of a substance by the kidneys per unit time." and in blue italic: "C = (U × V) / P where U = urine concentration, V = urine flow rate, P = plasma concentration" Left column (3 sections stacked): Section 1 - green header with number 1: "THE CLEARANCE FORMULA" - Large formula box: C = [U]x × V / [P]x - Units: mL/min - Small table: C = Clearance (mL/min), [U] = Urine concentration (mg/mL), V = Urine flow rate (mL/min), [P] = Plasma concentration (mg/mL) - Small kidney diagram with arrows showing filtration, reabsorption, secretion Section 2 - blue header with number 2: "INULIN CLEARANCE = GFR" - Bold text: Normal GFR = 120 mL/min - Bullet points: Freely filtered at glomerulus, NOT reabsorbed, NOT secreted, Therefore C(inulin) = GFR exactly - Small glomerulus diagram with arrow labeled "filtered only" - Gold star badge: "Gold Standard for GFR" Section 3 - orange header with number 3: "CREATININE CLEARANCE" - Text: Clinical estimate of GFR - Normal: ~125 mL/min - Produced endogenously at constant rate - Slightly overestimates GFR (small tubular secretion) - No infusion needed - practical for clinical use - Small test tube icon Middle column: Section 4 - purple header with number 4: "PAH CLEARANCE = Renal Plasma Flow" - Large text: C(PAH) ≈ Effective RPF = 660 mL/min - PAH = Para-aminohippuric acid - Filtered AND completely secreted by proximal tubule - ~100% extracted in single pass through kidney - Formula box: RBF = RPF / (1 - Hematocrit) = ~1200 mL/min - Kidney diagram with artery and vein labeled, showing complete PAH extraction Section 5 - red header with number 5: "CLEARANCE RATIO (Fractional Excretion)" - Formula: Clearance Ratio = C(X) / C(inulin) - Three interpretation boxes: * Ratio = 1: Neither reabsorbed nor secreted (like inulin) * Ratio < 1: Net REABSORPTION by tubules * Ratio > 1: Net SECRETION by tubules - Example box with yellow background: Na+ example: C(Na+)/C(inulin) = 1.43/150 = 0.01 → 99% of filtered Na+ is REABSORBED Right column: Section 6 - teal header with number 6: "WHAT CLEARANCE REVEALS" - Arrow diagram showing: * C(X) < C(inulin) → Tubular REABSORPTION * C(X) = C(inulin) → Filtered only, no transport * C(X) > C(inulin) → Tubular SECRETION - Three substance icons with their clearance: Glucose = 0 (fully reabsorbed), Inulin = 120 (GFR marker), PAH = 660 (fully secreted) Section 7 - dark green header with number 7: "CLEARANCE RANGE TABLE" Colorful table: | Substance | Clearance | Mechanism | | Albumin | ~0 mL/min | Not filtered (too large) | | Glucose | ~0 mL/min | Filtered + fully reabsorbed | | Na+ | ~1.4 mL/min | Filtered + 99% reabsorbed | | Urea | ~70 mL/min | Filtered + partial reabsorption | | Inulin | 120 mL/min | Filtered only = GFR | | Creatinine | 125 mL/min | Filtered + slight secretion | | PAH | 660 mL/min | Filtered + fully secreted = RPF | Bottom dark navy bar - SUMMARY FLOW: Plasma → Glomerulus (Filtration) → Tubule (Reabsorption / Secretion) → Urine → Measure C = UxV/P → Compare to Inulin → Determine transport Bottom red bar - CLINICAL IMPORTANCE: • GFR < 60 mL/min for >3 months = Chronic Kidney Disease (CKD) • Creatinine clearance used to dose renally-cleared drugs • Inulin is gold standard but impractical clinically • Fractional excretion of Na+ (FENa) < 1% = Pre-renal AKI; >2% = Intrinsic renal AKI

A detailed medical educational flashcard poster titled "MICTURITION" in large bold white text on a dark navy blue banner at the top, same professional style as a medical physiology diagram. Top banner: Dark navy blue with "MICTURITION" in large bold white text. Below it a light yellow box: "Micturition is the process by which the urinary bladder empties when it becomes filled." Blue italic text: "Involves two steps: (1) Progressive bladder filling to threshold → (2) Micturition reflex causing bladder emptying" Left column: Section 1 - green header "1 ANATOMY OF THE BLADDER": - Labeled anatomical diagram of bladder showing: Body, Neck (posterior urethra), Trigone, Detrusor muscle, Internal sphincter (smooth, involuntary), External sphincter (skeletal, voluntary), Ureters entering at trigone - Text boxes: "Detrusor muscle - smooth muscle, contracts to raise pressure 40-60 mmHg", "Trigone - smooth triangular area on posterior wall", "Internal sphincter - maintained by sympathetic tone", "External sphincter - voluntary control via pudendal nerve" Section 2 - blue header "2 THE MICTURITION CYCLE": Two side-by-side colored boxes: LEFT box (light blue): "STORAGE PHASE (Filling)" • Low intravesical pressure • Normal compliance - viscoelastic bladder wall • No parasympathetic input to detrusor • Sympathetic system dominates (hypogastric nerve): - α-adrenergic: contracts bladder outlet - β3-adrenergic: relaxes detrusor - Inhibits parasympathetic ganglia • Pudendal nerve keeps external sphincter contracted • Pontine STORAGE centre active RIGHT box (light pink): "VOIDING PHASE (Emptying)" • Coordinated detrusor contraction • Parasympathetic activation (pelvic nerve, S2-S4) • Relaxation of bladder neck & external sphincter • Inhibition of sympathetic reflexes • Pontine MICTURITION centre activated • Voluntary relaxation of external sphincter Middle column: Section 3 - orange header "3 MICTURITION REFLEX - Step by Step": Numbered flowchart with arrows: 1. Bladder fills → Stretch receptors activated (bladder wall & posterior urethra) 2. Sensory signals via pelvic nerve → Sacral cord S2-S4 3. Reflex parasympathetic output → Detrusor contracts 4. Self-regenerating cycle: contraction → more stretch → more signals → stronger contraction 5. Three-phase cycle: (a) Rapid pressure rise → (b) Sustained pressure → (c) Return to baseline 6. Signals via pudendal nerve → External sphincter inhibited → Voiding occurs 7. After voiding: reflex fatigues → Bladder relaxes Section 4 - purple header "4 NEURAL CONTROL - Higher Brain Centers": Table with two columns: Brain Center | Function Cerebral cortex | Mainly inhibitory; voluntary control; facilitatory when voiding desired Pontine micturition center | Strong facilitatory; coordinates detrusor + sphincter relaxation Pontine storage center | Inhibitory; maintains continence during filling Periaqueductal grey (PAG) | Relay between cortex and pontine centers Sacral cord S2-S4 | Site of micturition reflex arc Text box: "Normal control: Higher centers keep reflex INHIBITED until convenient → Cortex voluntarily contracts external sphincter → When ready: cortex FACILITATES sacral centers + INHIBITS external sphincter" Right column: Section 5 - red header "5 NERVE SUPPLY SUMMARY": Three colored boxes: PARASYMPATHETIC (blue): Pelvic nerve, S2-S4, Contracts detrusor (voiding) SYMPATHETIC (yellow): Hypogastric nerve, T10-L2, Relaxes detrusor + contracts outlet (storage) SOMATIC (green): Pudendal nerve, S2-S4, Controls external sphincter (voluntary) Section 6 - dark red header "6 ABNORMALITIES OF MICTURITION": Three colored cards: Card 1 (red): "ATONIC BLADDER / OVERFLOW INCONTINENCE" Cause: Destruction of sensory nerve fibers (sacral crush injury, tabes dorsalis in syphilis) Result: Bladder fills to capacity → overflows in drops → no micturition reflex Card 2 (orange): "AUTOMATIC BLADDER" Cause: Spinal cord damage ABOVE sacral region (sacral cord intact) Result: Periodic unannounced bladder emptying, no voluntary control Card 3 (yellow): "UNINHIBITED NEUROGENIC BLADDER" Cause: Partial damage to spinal cord / brainstem - loss of inhibitory signals Result: Frequent uncontrollable urination - even small urine volumes trigger voiding Bottom dark navy bar - SUMMARY FLOW: Bladder fills → Stretch receptors activated → Pelvic nerve → Sacral cord (S2-S4) → Parasympathetic → Detrusor contracts + Sphincter relaxes → Voiding → Controlled by Pontine centers + Cerebral cortex Bottom red bar - CLINICAL IMPORTANCE: • Urinary incontinence: failure of storage phase - overactive detrusor or weak sphincter • Urinary retention: failure of voiding - underactive detrusor or outlet obstruction • Neurogenic bladder: any lesion in neural control pathway • Anticholinergics (e.g., oxybutynin) reduce detrusor overactivity • Urodynamic studies assess bladder pressure and flow during filling and voiding

A detailed medical educational flashcard poster titled "MICTURITION" in large bold white text on a dark navy blue banner at the top, same professional style as a RAAS medical physiology diagram. White background, colorful numbered sections, clean layout with icons and small diagrams. Top banner: Dark navy blue with "MICTURITION" in large bold white text. Below it a light yellow box: "Micturition is the process by which the urinary bladder empties when it becomes filled." Blue italic text below: "Two steps: (1) Progressive bladder filling to threshold → (2) Micturition reflex causing emptying + conscious desire to urinate" LEFT COLUMN (3 sections): Section 1 - green numbered badge "1" header "ANATOMY OF THE BLADDER": Simple labeled bladder diagram showing: Body (main storage), Neck/posterior urethra (2-3cm), Trigone (smooth triangular area), Detrusor muscle (smooth muscle, all directions), Internal sphincter (involuntary smooth muscle), External sphincter (voluntary skeletal muscle, pudendal nerve), Two ureters entering trigone. Small text notes: "Detrusor contraction raises pressure to 40-60 mmHg" Section 2 - blue numbered badge "2" header "STORAGE PHASE (Filling)": Light blue background box. Bullet points: - Low intravesical pressure (normal compliance) - No parasympathetic input to detrusor - Sympathetic dominates via Hypogastric nerve (T10-L2): alpha-adrenergic: contracts bladder outlet beta-3 adrenergic: relaxes detrusor Inhibits parasympathetic ganglia - Pudendal nerve: keeps external sphincter contracted - Pontine STORAGE centre maintains continence Small icon of bladder filling with closed outlet. Section 3 - pink numbered badge "3" header "VOIDING PHASE (Emptying)": Light pink background box. Bullet points: - Coordinated detrusor contraction - Parasympathetic activated via Pelvic nerve (S2-S4) - Relaxation of bladder neck and external sphincter - Sympathetic reflexes inhibited - Pontine MICTURITION centre activated - Voluntary relaxation of external sphincter Small icon of bladder emptying with open outlet and urine flow arrow. MIDDLE COLUMN (2 sections): Section 4 - orange numbered badge "4" header "MICTURITION REFLEX - Step by Step": Vertical numbered flowchart with colored arrows: Step 1 (blue box): Bladder fills → Stretch receptors activated in bladder wall and posterior urethra Arrow down Step 2 (green box): Sensory signals via Pelvic nerve → Sacral cord S2-S4 Arrow down Step 3 (orange box): Reflex parasympathetic output → Detrusor muscle contracts Arrow down (with loop arrow labeled "Self-regenerating cycle") Step 4 (red box): Contraction activates more stretch receptors → stronger signals → stronger contraction Arrow down Step 5 (purple box): Signals via Pudendal nerve → External sphincter inhibited → VOIDING Arrow down Step 6 (grey box): Reflex fatigues → Bladder relaxes → cycle resets Side note box: "Micturition reflex cycle: (a) Rapid pressure rise → (b) Sustained pressure → (c) Return to baseline" Section 5 - purple numbered badge "5" header "NERVE SUPPLY SUMMARY": Three colored horizontal bars: PARASYMPATHETIC (blue bar): Pelvic nerve | S2-S4 | Contracts detrusor → VOIDING SYMPATHETIC (yellow bar): Hypogastric nerve | T10-L2 | Relaxes detrusor, contracts outlet → STORAGE SOMATIC (green bar): Pudendal nerve | S2-S4 | Controls external sphincter → VOLUNTARY control RIGHT COLUMN (2 sections): Section 6 - teal numbered badge "6" header "HIGHER BRAIN CONTROL": Table: Brain Center | Role Cerebral cortex | Mainly INHIBITORY; voluntary control; facilitatory when voiding desired Pontine micturition centre | Strong FACILITATORY; coordinates detrusor contraction + sphincter relaxation Pontine storage centre | INHIBITORY; maintains continence during filling Periaqueductal grey (PAG) | Relay between cortex and pontine centres Text box with light yellow background: "Normal: Higher centres keep reflex INHIBITED → Cortex contracts external sphincter voluntarily → When ready to void: Cortex FACILITATES sacral centres + INHIBITS external sphincter" Section 7 - red numbered badge "7" header "ABNORMALITIES OF MICTURITION": Three stacked colored cards: Card 1 (red background): "ATONIC BLADDER / OVERFLOW INCONTINENCE" Cause: Destroyed sensory nerve fibers - sacral crush injury, tabes dorsalis (syphilis) Result: No micturition reflex → bladder fills to capacity → overflows in drops Card 2 (orange background): "AUTOMATIC BLADDER" Cause: Spinal cord damage ABOVE sacral region (sacral cord intact) Result: Periodic unannounced bladder emptying, no voluntary control Card 3 (yellow background): "UNINHIBITED NEUROGENIC BLADDER" Cause: Partial cord/brainstem damage - loss of inhibitory signals Result: Frequent uncontrollable urination; small urine volumes trigger voiding BOTTOM DARK NAVY SUMMARY FLOW BAR: Bladder fills → Stretch receptors → Pelvic nerve → Sacral cord S2-S4 → Parasympathetic → Detrusor contracts + Sphincter relaxes → Voiding → Modulated by Pontine centres + Cerebral cortex BOTTOM RED CLINICAL IMPORTANCE BAR: Urinary incontinence: overactive detrusor or weak sphincter (storage failure) | Urinary retention: underactive detrusor or obstruction (voiding failure) | Anticholinergics (oxybutynin) reduce detrusor overactivity | Neurogenic bladder: any lesion in neural control pathway

Medical educational flashcard poster for MICTURITION. Dark navy blue title banner at top with "MICTURITION" in large bold white text. Yellow info box below: "Micturition = bladder emptying process. Two steps: progressive filling to threshold, then micturition reflex." White background with 7 numbered colored sections arranged in 3 columns. Section 1 green - BLADDER ANATOMY: labeled diagram showing body, neck, detrusor muscle, trigone, internal sphincter (smooth/involuntary), external sphincter (skeletal/voluntary), ureters. Note: detrusor contraction raises pressure 40-60 mmHg. Section 2 blue - STORAGE PHASE: low intravesical pressure, sympathetic dominates (hypogastric nerve T10-L2), alpha-adrenergic contracts outlet, beta3-adrenergic relaxes detrusor, pudendal nerve keeps external sphincter contracted, pontine storage centre active, no parasympathetic input. Section 3 pink - VOIDING PHASE: parasympathetic activated (pelvic nerve S2-S4), detrusor contracts, bladder neck and external sphincter relax, sympathetic inhibited, pontine micturition centre activated. Section 4 orange - MICTURITION REFLEX STEPS: flowchart: Bladder fills → stretch receptors activated → pelvic nerve → sacral cord S2-S4 → parasympathetic → detrusor contracts (self-regenerating cycle) → pudendal nerve inhibited → external sphincter relaxes → voiding → reflex fatigues → reset. Section 5 purple - NERVE SUPPLY: three bars: Parasympathetic pelvic nerve S2-S4 voiding. Sympathetic hypogastric nerve T10-L2 storage. Somatic pudendal nerve S2-S4 voluntary sphincter control. Section 6 teal - HIGHER BRAIN CONTROL: table listing Cerebral cortex mainly inhibitory voluntary control, Pontine micturition centre facilitatory coordinates voiding, Pontine storage centre inhibitory maintains continence, PAG relay between cortex and pons. Section 7 red - ABNORMALITIES: three cards: Atonic bladder - sensory nerve destruction, overflow incontinence. Automatic bladder - cord damage above sacral level, unannounced voiding. Uninhibited neurogenic bladder - partial cord damage, frequent uncontrollable urination. Bottom navy summary flow bar: Filling → Stretch receptors → Sacral cord S2-S4 → Detrusor contracts + Sphincter relaxes → Voiding → Controlled by Pontine centres and Cortex. Bottom red clinical bar: Incontinence = storage failure. Retention = voiding failure. Anticholinergics reduce detrusor overactivity. Neurogenic bladder from any neural lesion.

A detailed medical educational flashcard poster titled "THE NEPHRON" in large bold white text on a dark navy blue banner at the top, same professional style as a RAAS medical physiology diagram. White background, colorful numbered sections with icons and diagrams, clean layout. Top banner: Dark navy blue with "THE NEPHRON" in large bold white text. Yellow info box below: "The nephron is the structural and functional unit of the kidney. Each kidney contains approximately 1 million nephrons." Blue italic text: "Two types: Cortical nephrons (85%) — short loop of Henle | Juxtamedullary nephrons (15%) — long loop of Henle, important for concentration" LEFT COLUMN (3 sections): Section 1 - green badge "1" - STRUCTURE OF THE NEPHRON: Large central detailed diagram of a single nephron showing all labeled parts in sequence: - Bowman's capsule (surrounds glomerulus) - Glomerulus (capillary tuft) - Proximal Convoluted Tubule (PCT) - Loop of Henle: Descending limb, Thin ascending limb, Thick ascending limb - Distal Convoluted Tubule (DCT) - Collecting Duct - Afferent arteriole (blood in) and Efferent arteriole (blood out) - Peritubular capillaries around tubules - Vasa recta alongside loop of Henle Cortex and Medulla regions labeled with a dividing line. Section 2 - blue badge "2" - BOWMAN'S CAPSULE AND GLOMERULUS: Small glomerulus diagram. - Glomerulus: tuft of capillaries, high-pressure filtration - Filtration barrier: Fenestrated endothelium + Basement membrane + Podocytes (filtration slits) - Filters ~180 L/day of plasma (GFR = 120 mL/min) - Filters: water, ions, glucose, urea, amino acids - Does NOT filter: proteins, blood cells (too large) - Bowman's capsule collects the filtrate Section 3 - orange badge "3" - PROXIMAL CONVOLUTED TUBULE (PCT): Location: Cortex Key functions: - Reabsorbs 65-70% of filtered Na+, water, Cl- - Reabsorbs 100% of filtered glucose and amino acids (active transport) - Reabsorbs HCO3- (bicarbonate) - Secretes H+, organic acids, drugs, toxins - Isotonic reabsorption (osmolarity unchanged) - Most important site of tubular reabsorption MIDDLE COLUMN (3 sections): Section 4 - purple badge "4" - LOOP OF HENLE: Diagram of loop showing descending and ascending limbs. Two sub-boxes: DESCENDING LIMB (blue): Permeable to WATER only, Impermeable to solutes, Water exits by osmosis → tubular fluid becomes concentrated (hyperosmotic) ASCENDING LIMB (red): Impermeable to WATER, Actively transports Na+, K+, Cl- out (NKCC2 cotransporter), Dilutes tubular fluid → fluid becomes hypotonic Function: Creates medullary osmotic gradient (countercurrent multiplication). Juxtamedullary nephrons essential for concentrating urine up to 1200 mOsm/kg. Section 5 - teal badge "5" - DISTAL CONVOLUTED TUBULE (DCT): Location: Cortex Key functions: - Fine-tuning of Na+ and Cl- reabsorption (NCC cotransporter) - Ca2+ reabsorption (regulated by PTH) - Macula densa cells here sense NaCl delivery → regulate GFR (tubuloglomerular feedback) - Aldosterone acts here: increases Na+ reabsorption, K+ excretion - Site of action: Thiazide diuretics block NCC Section 6 - red badge "6" - COLLECTING DUCT: Location: Cortex → Medulla Key functions: - Final regulation of urine concentration - Principal cells: ADH increases water permeability (aquaporin-2 insertion) → concentrated urine - Without ADH: collecting duct impermeable to water → dilute urine - Intercalated cells: H+ secretion (acid-base balance), HCO3- reabsorption - Aldosterone: Na+ reabsorption, K+ excretion in principal cells - Site of action: Loop diuretics (furosemide), Potassium-sparing diuretics RIGHT COLUMN (2 sections): Section 7 - dark green badge "7" - BLOOD SUPPLY OF NEPHRON: Diagram showing vascular relationships: Renal artery → Interlobar artery → Arcuate artery → Interlobular artery → Afferent arteriole → Glomerular capillaries → Efferent arteriole → Peritubular capillaries (cortical nephrons) OR Vasa recta (juxtamedullary nephrons) → Venous drainage Key note: Efferent arteriole has HIGH resistance → maintains glomerular filtration pressure Section 8 - dark red badge "8" - SUMMARY TABLE OF NEPHRON SEGMENTS: Clean colorful table: Segment | Location | % Reabsorbed | Key Ions/Molecules | Special Features Glomerulus | Cortex | Filtration only | Water, Na, glucose, urea | GFR 120 mL/min PCT | Cortex | 65-70% | Na, water, glucose, AA, HCO3 | Bulk reabsorption, isotonic Descending Loop | Medulla | Water only | Water | Concentrated tubular fluid Ascending Loop | Medulla | Na, K, Cl | Na/K/Cl (NKCC2) | Impermeable to water DCT | Cortex | 5-10% | Na, Cl, Ca | PTH, Aldosterone, Thiazides Collecting Duct | Cortex+Medulla | Variable | Water (ADH), Na (Aldosterone) | Final concentration BOTTOM DARK NAVY SUMMARY FLOW BAR: Blood enters Afferent arteriole → Glomerular filtration (Bowman's capsule) → PCT (bulk reabsorption) → Loop of Henle (concentration gradient) → DCT (fine-tuning) → Collecting duct (final concentration by ADH/Aldosterone) → Urine excreted BOTTOM RED CLINICAL IMPORTANCE BAR: Diabetes mellitus: glucose appears in urine when plasma glucose exceeds tubular maximum (Tm ~180 mg/dL) | Nephrotic syndrome: damaged filtration barrier → protein in urine | Loop diuretics (furosemide): block NKCC2 in thick ascending limb | Thiazides: block NCC in DCT | ADH deficiency: Diabetes insipidus → large volume dilute urine | ACE inhibitors: dilate efferent arteriole → reduce GFR → renoprotective

Medical educational flashcard poster "THE NEPHRON" in bold white text on dark navy blue banner. Yellow subtitle box: "Structural and functional unit of the kidney. Each kidney has ~1 million nephrons. Two types: Cortical nephrons 85% short loop, Juxtamedullary nephrons 15% long loop for urine concentration." White background, 8 numbered colored sections in 3 columns, professional medical diagram style. Section 1 green - NEPHRON STRUCTURE: Large labeled nephron diagram showing Bowman capsule, Glomerulus, PCT, Loop of Henle descending and ascending limbs, DCT, Collecting duct, Afferent and efferent arterioles, Peritubular capillaries, Vasa recta. Cortex and Medulla regions labeled. Section 2 blue - GLOMERULUS AND FILTRATION: Filtration barrier: fenestrated endothelium, basement membrane, podocyte filtration slits. Filters 180 L per day, GFR 120 mL/min. Filters water, ions, glucose, urea. Does NOT filter proteins or blood cells. Section 3 orange - PROXIMAL CONVOLUTED TUBULE PCT: Located in cortex. Reabsorbs 65-70% Na and water, 100% glucose and amino acids by active transport, bicarbonate. Secretes H+, drugs, toxins. Isotonic reabsorption. Most important reabsorption site. Section 4 purple - LOOP OF HENLE: Descending limb: permeable to water only, fluid becomes concentrated hyperosmotic. Ascending limb: impermeable to water, actively transports Na K Cl out via NKCC2 cotransporter, fluid becomes dilute hypotonic. Creates medullary osmotic gradient by countercurrent multiplication up to 1200 mOsm. Section 5 teal - DISTAL CONVOLUTED TUBULE DCT: Located in cortex. Reabsorbs Na and Cl via NCC cotransporter. Ca2+ reabsorption regulated by PTH. Macula densa senses NaCl for tubuloglomerular feedback. Aldosterone increases Na reabsorption and K excretion. Thiazide diuretics act here. Section 6 red - COLLECTING DUCT: Final urine concentration. Principal cells: ADH inserts aquaporin-2 channels, water reabsorbed, concentrated urine. Without ADH: dilute urine. Intercalated cells: H+ secretion, acid-base balance. Aldosterone acts on principal cells. Loop diuretics and potassium-sparing diuretics act here. Section 7 dark green - BLOOD SUPPLY: Renal artery to afferent arteriole to glomerular capillaries to efferent arteriole to peritubular capillaries for cortical nephrons or vasa recta for juxtamedullary nephrons then venous drainage. Efferent arteriole high resistance maintains filtration pressure. Section 8 navy table - SEGMENT SUMMARY TABLE: columns Segment, Location, Key reabsorption, Special function. Rows: Glomerulus cortex filtration only GFR marker. PCT cortex 65% Na water glucose amino acids bulk reabsorption. Descending loop medulla water only concentrates fluid. Ascending loop medulla Na K Cl dilutes fluid impermeable to water. DCT cortex Na Cl Ca fine tuning aldosterone PTH. Collecting duct cortex medulla water by ADH Na by aldosterone final concentration. Bottom navy flow bar: Afferent arteriole → Glomerular filtration → PCT bulk reabsorption → Loop of Henle osmotic gradient → DCT fine tuning → Collecting duct ADH aldosterone → Urine output. Bottom red clinical bar: Glucosuria when plasma glucose exceeds Tm 180 mg/dL. Furosemide blocks NKCC2 ascending loop. Thiazides block NCC DCT. ADH deficiency causes diabetes insipidus. Nephrotic syndrome damages filtration barrier causing proteinuria.

Medical education poster titled THE NEPHRON on dark navy blue top banner with white bold text. Below banner a yellow box: Structural and functional unit of the kidney. 1 million nephrons per kidney. Cortical nephrons 85 percent, Juxtamedullary nephrons 15 percent. Six colorful numbered sections on white background in two columns. Left column top - green section 1 NEPHRON STRUCTURE: labeled diagram of nephron with Bowman capsule, glomerulus, proximal convoluted tubule PCT, loop of Henle with descending and ascending limbs, distal convoluted tubule DCT, collecting duct, afferent arteriole, efferent arteriole, peritubular capillaries, vasa recta. Cortex above medulla below with dotted line. Left column middle - blue section 2 GLOMERULUS AND FILTRATION: Filtration membrane has three layers: fenestrated endothelium, glomerular basement membrane, podocyte foot processes. GFR equals 120 mL per min, filters 180 L per day. Filters small molecules: water, ions, glucose, urea, amino acids. Does NOT filter proteins or red blood cells. Left column bottom - orange section 3 PROXIMAL CONVOLUTED TUBULE: Cortex location. Reabsorbs 65 to 70 percent of Na and water. Reabsorbs 100 percent glucose and amino acids by sodium cotransport. Reabsorbs bicarbonate. Secretes H+, drugs, creatinine. Most important site of reabsorption. Isotonic fluid. Right column top - purple section 4 LOOP OF HENLE: Two parts. Descending thin limb: water permeable only, fluid concentrates, osmolarity rises to 1200 mOsm. Ascending thick limb: impermeable to water, NKCC2 cotransporter pumps Na K Cl out, fluid dilutes to 100 mOsm. Creates countercurrent multiplication gradient in medulla. Vasa recta maintains gradient. Right column middle - red section 5 DCT AND COLLECTING DUCT: DCT in cortex: NCC cotransporter reabsorbs NaCl, PTH increases Ca reabsorption, aldosterone increases Na reabsorption and K secretion, thiazide diuretics block NCC here. Collecting duct: ADH inserts aquaporin 2 channels for water reabsorption giving concentrated urine, without ADH urine is dilute, intercalated cells regulate acid base by secreting H+ and reabsorbing bicarbonate, aldosterone acts on principal cells. Right column bottom - dark green section 6 DIURETICS AND CLINICAL POINTS: Table with three rows. Furosemide loop diuretic blocks NKCC2 in ascending limb. Thiazide diuretic blocks NCC in DCT. Spironolactone blocks aldosterone in collecting duct. Clinical notes: Glucosuria when blood glucose over 180 mg/dL exceeds tubular max. Diabetes insipidus when ADH absent causes large dilute urine. Nephrotic syndrome damages filtration barrier causes proteinuria. Bottom dark navy summary flow arrow bar: Blood enters afferent arteriole → Glomerulus filtration GFR 120 → PCT bulk reabsorption 65 percent → Loop of Henle countercurrent gradient → DCT fine tuning → Collecting duct ADH aldosterone → Final urine excreted. Bottom red clinical importance bar: GFR less than 60 for 3 months equals CKD. FENa less than 1 percent equals prerenal AKI. Furosemide blocks ascending loop. ADH absent equals diabetes insipidus. Aldosterone excess causes hypertension and hypokalemia.