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Flashcards: Fuel and Waste- Unit 4
• Afferent Arteriole
Vessel carrying blood to the glomerulus.
• Efferent Arteriole
Vessel carrying blood away from the glomerulus.
• Bowman’s Capsule
Structure surrounding the glomerulus where filtration begins.
• Glomerulus
Capillary network where blood is filtered.
• Glomerular Filtration Rate (GFR)
Rate at which blood is filtered in the kidneys.
• Nephron
Functional unit of the kidney responsible for filtration, reabsorption, and excretion.
• Loop of Henle
U-shaped portion of the nephron that establishes a concentration gradient for water reabsorption.
• Proximal Convoluted Tubule
First section of the nephron, involved in reabsorption of water, ions, and nutrients.
• Distal Convoluted Tubule
Last nephron segment before collecting duct; involved in selective reabsorption and secretion.
• Collecting Duct
Tubule where final adjustments to urine composition are made.
• Vasa Recta
Capillaries parallel to the Loop of Henle that maintain osmotic gradient.
• Renal Corpuscle
Combination of the glomerulus and Bowman’s capsule.
• Renal Cortex
Outer portion of the kidney containing nephrons.
• Renal Medulla
Inner kidney region where loops of Henle are located.
• Renal Pelvis
Central collecting area for urine before it exits the kidney.
• Renal Artery/Vein
Blood vessels delivering and removing blood from the kidney.
• Urine
Waste product of the kidneys excreted via the urinary tract.
• Bladder
Organ for urine storage.
• Ureter
Tube carrying urine from the kidney to the bladder.
• Urethra
Tube through which urine exits the body.
• Urinary Tract Infection (UTI)
Infection in any part of the urinary system.
• Vasopressin (ADH)
Hormone regulating water reabsorption in the kidney.
• Mouth
Site of ingestion and beginning of digestion.
• Salivary Glands
Exocrine glands producing saliva to begin digestion.
• Amylase
Enzyme in saliva that breaks down carbohydrates.
• Esophagus
Tube carrying food from mouth to stomach.
• Epiglottis
Flap preventing food from entering the trachea during swallowing.
• Stomach
Organ for mechanical digestion and initial protein digestion via enzymes and acid.
• Chyme
Partially digested food leaving the stomach.
• Small Intestine
Primary site of nutrient digestion and absorption, consisting of the duodenum, jejunum, and ileum.
• Duodenum
First section where most chemical digestion occurs.
• Jejunum
Middle section specializing in nutrient absorption.
• Ileum
Final section absorbing bile salts and vitamins.
• Colon (Large Intestine)
Absorbs water and forms feces.
• Rectum
Final segment for fecal storage before defecation.
• Defecation Reflex
Neural reflex controlling bowel movements.
• Liver
Produces bile, detoxifies substances, and processes nutrients.
• Gallbladder
Stores and concentrates bile for fat digestion.
• Bile Salts
Components of bile aiding in fat emulsification.
• Pancreas
Secretes digestive enzymes and bicarbonate ions into the duodenum.
• Gastric Glands
Stomach glands secreting acid and enzymes.
• Parietal Cells
Stomach cells secreting hydrochloric acid (HCl).
• Chief Cells
Stomach cells secreting pepsinogen, which becomes pepsin to digest proteins.
• Protease
General term for enzymes breaking down proteins.
• Lipase
Enzyme breaking down fats.
• Lacteal
Lymphatic capillaries in villi that absorb dietary fats.
• Enterocyte
Absorptive cells lining the small intestine.
• Rugae
Folds in the stomach allowing expansion.
• Mucus
Secretion protecting and lubricating the GI tract.
• Sphincters
Muscle rings controlling passage of food or waste between sections of the GI tract.
• Autoregulation
Ability of organs (e.g., kidney) to maintain constant function despite changes in blood pressure.
• Excretion
Removal of waste products from the body.
• Secretion
Active transport of substances into tubules or GI tract.
• Filtration
Passive movement of substances from blood into the nephron.
• Reabsorption
Return of filtered substances from the nephron to the blood.
• Portal Systems
Venous systems connecting capillary beds, such as the hepatic portal system.
o Motility
Peristalsis (wave-like contractions) and segmentation (mixing movements).
o Digestion
Breakdown of food (mechanical vs. chemical).
o Secretion
Release of digestive enzymes and fluids.
o Absorption
Uptake of nutrients into the bloodstream or lymph.
o Path of blood
Renal artery → Afferent arteriole → Glomerulus → Efferent arteriole → Peritubular capillaries → Renal vein.
o Path of filtrate
Bowman’s capsule → Proximal tubule → Loop of Henle → Distal tubule → Collecting duct → Renal pelvis → Ureter.
o Countercurrent Exchange
Mechanism in the Loop of Henle and vasa recta to concentrate urine.
o Aldosterone
Stimulates sodium reabsorption, increasing water retention.
o Vasopressin (ADH)
Promotes water reabsorption in the collecting ducts.