Biology Project: Urinary System

For this last term, our biology teacher gave us a creative project to work on. This consisted on making a model of the urinary system with trash. To make this model, we went through a large process. First, all throughout the weekend we looked up for things that we thought it could be useful to our project like for example can of coke, sponges, caps and straws. We collected many things but we didn’t use all of them. It was not easy for us to decide which element was the correct one for each organ because we had to choose the one that fitted better for each. After a long time of research we had decided how our project would be. Carefully we started pasting all the objects we had chosen previously. We used an old sponge for the two kidneys. We cut the sponge in two equal pieces to form to kidneys that are identically to each other. Then, we used a big cup of jam to create the bladder. Furthermore, to make the urethra we used small caps of cokes and water that we had recycled. Moreover, we used many straws to make the aorta and the vena cava. To give color to both of them we covered the straws with elastic bands red and blue. And to make the renal artery and the renal vein we also used old elastic bands. To conclude, we made the urethra with an old wine cork. We cut it into two and used one half to make the organ. After all this work, we started to label each organ so that any person that looks at our project could recognize each of the organs. Finally, our project is know ready to present, here is a picture of it! Hope you like our work!

Functions of the organs:


  • The kidneys are two organs found on the left and right sides of the body in vertebrates. They are located near the middle of your back, just below the ribcage. They receive blood from the paired renal arteries; blood exits into the paired renal veins. Each kidney is attached to a ureter, a tube that carries excreted urine to the bladder. Kidneys produce hormones, absorb minerals, flitter blood and produce urine. Every kidneys process about 200 quarts of blood to sift out about 2 quarts of waste products and extra water. The waste and extra water become urine, which flows to your bladder through tubes called ureters. Each adult kidney contains around one million nephrons.


  • The ureter is a tube that carries urine from the kidney to the urinary bladder. There are two ureters, one attached to each kidney. The upper half of the ureter is located in the abdomen and the lower half is located in the pelvic area. The ureter is about 10 to 12 inches long in the average adult. The tube has thick walls composed of a fibrous, a muscular, and a mucus coat, which are able to contract.


  • The bladder, also known as the urinary bladder, is an expandable muscular sac that stores urine before it is excreted out of the body through the urethra. It is located in the lower abdominal area near the pelvic bones.
  • Urine is made in the kidneys, and travels down two tubes called ureters to the bladder. The bladder stores urine, allowing urination to be infrequent and voluntary.
  • During urination, the bladder muscles contract, and two sphincters (valves) open to allow urine to flow out.


  • In both genders, the urethra works as a tube connecting the urinary bladder to the genitals. The bladder collects and stores urine until it is ready to be discharged through the urethra. 


  • The male urethra connects the urinary bladder to the penis. Once the bladder becomes full, urine flows through the urethra and leaves the body at the urethral meatus, which is located at tip of the penis. The urethra is more than just a urinary duct; it also serves as a conduit for semen and sperm during sexual acts.


  • The female urethra is quite a bit shorter than its male counterpart and its opening is situated between a woman’s clitoris and vagina.

Renal vein:

  • There are two renal veins, a left and a right. They branch off the inferior vena cava and take away (drain)  deoxygenated blood ( without oxygen) from the kidneys. As they enter the kidneys, each vein separates into two parts. The posterior veins assist in draining ( taking away) the back section of each kidney, while the anterior veins assist the front part. These veins also are responsible for draining blood from the ureter, which transports urine away from the kidneys to the urinary bladder.

Renal Arteries:

  • There are two blood vessels leading off from the abdominal aorta that go to the kidneys. The renal artery is one of these two blood vessels. The renal artery enters through the hilum, which is located where the kidney curves inward in a concave shape. Under normal circumstances, once the renal artery enters through the hilum, it splits into two main branches, which each then split into numerous smaller arteries, which deliver blood to different areas of the kidneys, known as nephrons. Once the blood has been processed here, it is sent back through the renal vein to the inferior vena cava and to the right side section of the heart.

Abdominal Aorta:

  • The aorta supplies the blood that is being filtered by the kidneys. Because the blood is being filtered by the kidneys, it’s important that they be located somewhere that a lot of blood can filter through, and that a sufficiently big artery run through it. This is why the kidneys are located just below the ribs in the upper abdomen and that a major branch of the aorta runs through.

Inferior vena cava

  • The inferior vena cava is a large vein that carries de-oxygenated blood from the lower body to the heart. De-oxygenated blood means most of the oxygen has been removed by tissues, and therefore the blood is darker.
  • Its walls are rigid and has valves so the blood does not flow down via gravity.

I have worked with Juana Zufriategui and this is our project: