Excretion: The Body's Clean-Up Crew PDF

Excretion: The Body’s Clean-Up Crew How Your Kidneys, Lungs, and Skin Team Up to Keep You Fresh and Balanced  Table of contents 01 02 03 Lungs Intro to Excretion Kidneys 04 05 06 The Skin...

Excretion: The Body’s Clean-Up Crew How Your Kidneys, Lungs, and Skin Team Up to Keep You Fresh and Balanced  Table of contents 01 02 03 Lungs Intro to Excretion Kidneys 04 05 06 The Skin The Liver Large Intestines  01 Intro to Excretion The Basics Excretion defined: Removal of metabolic waste products to maintain homeostasis It's how your body kicks out the trash Kidneys: Excess water, urea, and salts (as (aka metabolic waste) urine). Excretion = keeping the body clean. Lungs: Carbon dioxide and a bit of water Removes toxins, excess water, and waste vapour (through breathing). (e.g., CO2, urea). Skin: Sweat (water, salts, urea). Excretion in humans is carried through Liver: Toxins and old red blood cells (through different body parts and internal organs bile). in a series of processes. Large Intestine: Solid waste (feces).  02 Kidneys If kidneys were a club, they'd be the bouncers letting the good stuff in and kicking the bad stuff out.  Kidneys – The Body's Bouncers Kidneys play a key role in filtering the Regulation of Electrolyte Balance: Controls blood and producing urine. salts like sodium and potassium levels. Two bean-shaped organs located in the Acid-Base Balance: Maintains pH of the blood. lower back. Production of Hormones: Erythropoietin Filtration of Blood: Removes waste and (stimulates red blood cell production), Renin excess substances. (regulates blood pressure). Regulation of Water Balance: Maintains hydration levels.  Inside the Kidneys Renal Cortex: Outer layer where filtration happens. Renal Medulla: Inner layer that contains the collecting ducts. Nephrons: Functional units responsible for filtering blood. ○ Glomerulus: A network of capillaries where filtration starts. ○ Bowman’s Capsule: Surrounds the glomerulus and collects filtered fluid. ○ Proximal Convoluted Tubule: Reabsorbs useful substances like glucose and salts. ○ Loop of Henle: Helps concentrate urine by reabsorbing water. ○ Distal Convoluted Tubule: Further regulates the composition of urine. ○ Collecting Duct: Final passage for urine before it enters the renal pelvis.  Urine Formation Filtration: Blood enters the glomerulus, where From Filtrate to Urine waste (urea, salts) is filtered into the Bowman’s Primary Filtrate: Initially consists of water, salts, capsule. glucose, and waste. Reabsorption: Useful substances like water, After Reabsorption: The remaining fluid is glucose, and salts are reabsorbed into the mostly waste, excess water, and toxins. bloodstream. Urine: The final product that exits the kidneys Secretion: Additional waste products (e.g., is stored in the bladder. drugs, hydrogen ions) are secreted into the nephron. Excretion: The final filtrate (urine) passes through the collecting duct into the renal pelvis and the ureter.  03 Lungs "Every exhalation contains a trace of your life’s story!“ CO₂ and other compounds in your breath can reveal metabolism, diet, and even stress levels.  Lungs Excretory Products of the Lungs Process of Excretion in the Lungs Carbon Dioxide (CO₂): Produced during Step 1: CO₂ diffuses from the cells into the cellular respiration (breakdown of glucose for bloodstream. energy).Transported to the lungs via the Step 2: Blood transports CO₂ to the lungs (via blood. red blood cells and plasma). Water Vapour (H₂O): A small amount is lost Step 3: CO₂ diffuses into the alveoli (tiny air during exhalation. sacs in the lungs). Breathing Rate: Controlled by the medulla Step 4: CO₂ and water vapour are exhaled oblongata in the brain. Increases during when breathing. exercise or high CO₂ levels in the blood. Gas Exchange Efficiency: Affected by lung health and environmental factors.  04 The Skin Sweating It Out  The Skin The skin eliminates waste products through Process of Excretion by the Skin sweat glands. It supports the kidneys in Step 1: Waste products are transported to maintaining water and salt balance. sweat glands via blood. Sweat Composition: Step 2: Sweat glands produce sweat containing Water: The primary component of water, salts, and small amounts of urea. sweat. Salts: Sodium chloride and other Step 3: Sweat is released onto the skin surface electrolytes. Urea and Ammonia: By-products of through pores. protein metabolism. Step 4: Evaporation of sweat helps cool the body while removing waste. Controlled by the Hypothalamus: Detects body temperature changes and triggers sweating.  05 The Liver Detoxification HQ "The Liver Can Regenerate!“ Even if 75% of the liver is damaged, it can repair itself over time.  The Liver Largest internal organ in the body. Plays a Process of Excretion by the Liver central role in metabolism, detoxification, and Blood Detoxification: Toxins and drugs are excretion. chemically altered (e.g., alcohol to Bile: Contains bilirubin (from the breakdown of acetaldehyde). haemoglobin) and bile salts. Bile Production: Waste products like bilirubin Urea: Formed during the breakdown of amino are secreted into bile. acids in the urea cycle. Elimination via Bile: Bile is transported to the Toxins and Drugs: Neutralized or converted gallbladder and then into the intestines. into less harmful substances for excretion. Excretion through Feces: Bilirubin gives faeces Regulation of Liver excretion is influenced by its characteristic brown colour. hormones and enzymes (CYP450 )  06 Large Intestines The Final Stop for Solid Waste  Large Intestines Solid Waste (Feces): Undigested food (e.g., Process of Excretion by the Large fibre).Dead cells from the lining of the Intestine digestive tract. Process of Excretion by the Large Intestine Bacterial Waste Products: Compounds like Absorption of Water and Salts: Removes water methane and hydrogen sulfide (cause odour). from the indigestible food residue. Converts Composition of Feces - Water: ~75%Solids: liquid chyme into solid faeces. ~25%Fiber and undigested food. Bacteria and Movement of Waste: Peristalsis moves faeces dead cells. Metabolic waste (e.g., stercobilin to the rectum. gives brown colour). Storage in the Rectum: Faeces are stored until System Control: Defecation reflex is triggered elimination. when rectum is stretched. Defecation: Waste is expelled through the Diet and Hydration anus.  CONCLUSION Excretion is a vital biological process that maintains homeostasis by removing metabolic waste products from the body. The primary excretory products include ammonia, urea, uric acid, carbon dioxide, and excess salts and water. These substances are eliminated through various excretory organs such as the kidneys, lungs, skin, and liver. The process of excretion involves filtration, reabsorption, secretion, and elimination, primarily regulated by the kidneys in humans. Hormones like antidiuretic hormone (ADH), aldosterone, and atrial natriuretic peptide (ANP) play crucial roles in maintaining water and electrolyte balance. Efficient excretory mechanisms ensure the proper functioning of the body, preventing toxic accumulation and promoting overall health.  REFERENCES Guyton, A. C., & Hall, J. E. (2021). Textbook of medical physiology (14th ed.). Elsevier. Marieb, E. N., & Hoehn, K. (2018). Human anatomy & physiology (11th ed.). Pearson. Sherwood, L. (2015). Human physiology: From cells to systems (9th ed.). Cengage Learning. Tortora, G. J., & Derrickson, B. (2020). Principles of anatomy and physiology (16th ed.). Wiley. Hall, J. E. (2021). Guyton and Hall textbook of medical physiology (14th ed.). Elsevier. Marieb, E. N., & Hoehn, K. (2018). Human anatomy & physiology (11th ed.). Pearson. Sherwood, L. (2015). Human physiology: From cells to systems (9th ed.). Cengage Learning. Tortora, G. J., & Derrickson, B. (2020). Principles of anatomy and physiology (16th ed.). Wiley. Ganong, W. F. (2019). Review of medical physiology (26th ed.). McGraw-Hill Education.  GROUP MEMBERS NAME INDEX NUMBER 1. Monney Stefan 11358535 2 Dwamena Roland Asamoah 11356519 3.Okosso Emmanuella 11353388 4. Hajara Ali 11352962 5. Dei Anane 6. ⁠Samuel 11356567 6. Yaw Owusu 11354599 7. Krakah Henry Kofi 11357107 8. Owusu Gideon Sarpong 11356700 9. Gbetivi Martina Elikplim 11354593 10. Nafisa Moro 11354372 11. Kafumawu Abla Droefenu 11356674 THANK YOU!!!!