<p> 1</p><p>Name:</p><p>Sheep Kidney and Fetal Pig Excretory System Lab</p><p>Part A – Dissection of fetal pig</p><p>Locate the kidneys along the back wall of the pig’s abdominal cavity. Find the ureters which lead downward to the urinary bladder. You may also be able to find the urethra which leads from the urinary bladder to the outside of the body.</p><p>1. Draw the urinary system of the pig below. Label the parts listed above Write the function of each part by its label.</p><p>2. What processes produce nitrogenous wastes?</p><p>3. How do flatworms such as planarians get rid of nitrogenous waste?</p><p>4. How do planarians maintain osmotic balance?</p><p>5. How do earthworms get rid of nitrogenous wastes and maintain water balance?</p><p>6. How do insects get rid of nitrogenous wastes and maintain water balance? 2</p><p>B. Dissection of the sheep kidney</p><p>Locate the ureter coming from the kidney.</p><p>Slice your kidney in half as shown by your teacher. Locate the outer portion of the kidney, which is called the renal cortex. Locate the inner solid portion of the kidney, which is the renal medulla. The central space inside the kidney is the renal pelvis.</p><p>1. Draw the sliced open kidney. Label the renal cortex, renal medulla, renal pelvis and ureter.</p><p>You may remove a kidney and slice it open, try to locate the renal cortex, medulla and pelvis.</p><p>2. What is the small filtering unit inside the kidney called?</p><p>3. What parts of the nephron are located in the renal cortex?</p><p>4. What parts of the nephron are located in the renal medulla?</p><p>5. Where does the liquid found in the nephron come from originally?</p><p>6. What happens at the glomerulus?</p><p>7. How does the filtrate entering the glomerulus differ from the blood in the capillary of the glomerulus?</p><p>8. How is the filtrate changed as it moves through the proximal tubule? 3</p><p>9. Draw a large nephron in the space below: Label the glomerulus, proximal tubule, distal tubule, collecting duct, descending loop of Henle and ascending loop of Henle. Identify where the cortex, inner and outer medulla are located. Draw arrows and name the materials that are moved in and out at various points as filtrate moves through the nephron. Use one color for active transport and another color for materials that are moved by diffusion.</p><p>10. Why is salt moved out along the ascending loop of Henle and collecting duct and why must it become more concentrated as you go inward through the medulla.?</p>