Body Fluids - SEC 1 LEVEL 2 DELTA - PDF

Body fluids chemistry Dr. Basma Salama Lecturer of biochemistry and molecular biology Body fluids What is body fluid? Literally, body fluid is the fluid of the body. A body fluid refers to any fluid produced by a living organism. The adult...

Body fluids chemistry Dr. Basma Salama Lecturer of biochemistry and molecular biology Body fluids What is body fluid? Literally, body fluid is the fluid of the body. A body fluid refers to any fluid produced by a living organism. The adult human body is ~50-60% composed of water.  Intracellular fluid (ICF) – located within the cell Extracellular fluid (ECF)–located outside the cell Interstitial fluid the fluid filling up the spaces between cells. Intravascular fluid (Blood plasma) Transcellular fluid (the fluid filling up the spaces of chambers formed from the linings of the epithelial cells) such as pericardial fluid, gastric and GIT fluid, synovial fluid etc. What is the function of body fluids? body fluids collection and analysis Diagnosis then Treatment Urine analysis  Urinary system Urine formation Urine formation process: 1. Filtration 2. Reabsorption 3. excretion Nephrons 1-Glomerular filtration: filtration pressure = renal blood pressure - (osmotic pressure of plasma proteins + pressure in bowman capsule) Collecting duct Renal pelvis 2-Tubular reabsorption Where the most of water and all wanted substances in the filtrate are transported from the tubules back to the blood of peritubular capillaries. Usually more than 99% of water and sodium in the glomerular filtrate are reabsorbed About 80-85% of water is reabsorbed from the proximal convoluted tubules under the effect of concentration gradient (Passive diffusion) and the rest under the effect of antidiuretic hormone from distal convoluted tubule. About 80-85% of sodium is reabsorbed from the proximal convoluted tubules under the effect of active transport and the rest under the effect of aldosterone hormone from distal convoluted tubule. Why?!! Nearly all potassium is reabsorbed in combination with chloride from proximal convoluted tubule 3-Tubular secretion Where the unwanted substances are transported from the blood of peritubular capillaries to be excreted in urine like excess potassium, some creatinine, uric acid and many of foreign substances. Thank you !!