Question | Answer |
what is osmoregulation based on? | based largely on controlled movement of solutes between internal fluids and the external environment |
what are osmoconfromers? | they are isoomotic with their surroundings and do not regulate their osmolarity |
what are osmoregulators? | expend energy to control water uptake and loss in a hyperosmotic or hypoosmotic environment |
what are transport epithelia? | specialized cells that regulate solute movement |
what do excretory systems produce? | they produce urine by refining a filtrate derived from body fluids |
what are the functions of excretory systems? | - Filtration: pressure-filtering of body fluids
- Reabsorption: reclaiming valuable solutes
- Secretion: adding toxins and other solutes from the body fluids to the filtarte
- Excretion: removing the filtrate from the system |
what are nephrons the functional unit of? | mammalian kidney |
when does filtration occurs? | occurs as blood pressure forces fluid from the blood in the glomerulus into the lumen of Bowman's capsule |
what is the pathway of the filtrate? | From bowman's capsule, the filtrate passes through three regions of the nephron: the proximal tubule, the loop of Henle, andthe distal tubule |
when does filtrate becomes urine? | becomes urine as it flows through the mammalian nephron and collecting duct |
how does the mammalian kidney conserve water? | conserves water by producing urine that is much more concentrated than body fluids |
what do NaCl and urea contribute to? | contribute to the osmolarity of the interstitial fluid, which causes reabsorption of water in the kidney and concentrates the urine |