BIOB34H3 Lecture Notes - Lecture 7: Distal Convoluted Tubule, Renal Function, Renal Pelvis
Document Summary
Osmoregulation occurs via contractile vacuoles within pinacocytes. Active expansion (diastole) of the vacuole reduces hydrostatic pressure inside the vacuole, which leads to accumulation of water. Protonephridia are blind-ended excretory tubes that open to the outside of the organism. Flagellar movement (by flame cells) provides the driving force to move water and solutes from ecf into the lumen = filtration. Tube cells reabsorb needed substances = reabsorption. Has a pink digestive tract and white execratory tract. 3 parts , top opening is nephridopore, middle tract is tube cell and ends are flame cells tube cell has slits which acts as filter. Heart and kidney are very close to each other, heart plays role in filtering fluid and making urine. Heart acts like a tube cell (filter- reabsorb) End sac (coelomosac) -> site of filtration. Labyrinth -> site of water and solute reabsorption. Tubule (nephridial canal) > site of solute reabsorption only, found only in freshwater animals.
