Every term, in Biology, we carry out a determined project, each about different topics. In this last term, we were divided in pairs to create a model of the urinary system with trash or things that are no longer used. Once we finished it, we had to upload a picture of it to our blogs, and then explain the procedure and the involved organs’ functions. I did it along with Anouk De Laferrere this is our assignment:
During the week, we collected and cleaned trash we could use to represent the organs and different parts of the urinary system. To begin with, we used a cardboard box as a base to build our model. Then, we used two toilet paper tubes that we painted with brownish red to represent the kidneys. To represent the Aorta and Vena Cava we used straws which we glued together and painted in red and blue respectively. Then we used more straws to represent the Renal Veins and the Renal Arteries, connected to the kidneys. After that we used yellow threads of wool to represent the ureters which connected the kidneys with the bladder. We made the bladder with the inferior part of a pot of “Dulce de Leche” (caramel). We made the urethra with the middle part that we cut from the same pot and gave the shape of a cylinder. Finally we labelled all the organs and parts involved. In the following paragraph we will explain the functions of each of them: the kidneys, the renal vein, the renal artery, the ureters, the urethra and the bladder.
There are 2 kidneys in the human body. They are bean-shaped organs of a brownish red color found below the ribs, behind the abdomen and the intestines, at the sides of the vertebral column. They are formed from three parts; the cortex, the medulla and the pelvis. Once the body has absorbed what it needs from the food and drink it processes, the waste products from metabolism, toxic materials (urea formed by amino acids, with nitrogen) are sent from the liver to the kidneys. There these substances are filtered and flushed out of the body as urine. The kidneys, besides removing the waste of the body as urine, thery Their keep a stable balance of salts and other substances in the blood; and produce erythropoietin, hormone that aids the formation of red blood cells. The kidneys are formed by thousands of tiny tubules called nephrones through which urea is removed from blood. Each nephron consists of a glomerulus, a ball formed of capillaries, and a small tube called a renal tubule. Urine is formed by urea with water and other waste substances.
The waste fluid that is created in the liver and collected in the kidney is transferred into the urinary bladder, through the ureter tubes, where urine is temporarily stored until the individual urinates. The urinary bladder provides a short term store for urine, until it is removed from the body through the urethra. The bladder is a triangle-shaped organ located in the lower abdomen. It is held in place by ligaments attached to other organs and the pelvic bones. The bladder’s walls expand to store urine, and contract to eject urine.
The urethrais a tube that in males runs through the penis, and serves as a carrier of semen as well as urine and in females is shorter and is just above the vagina.
This tube allows urine to pass out the body. The brain signals the bladder to contract, squeezing urine out of the bladder. At the same time, the brain signals the sphincter muscle in the bladder, at the top of the urethra, to relax letting urine exit the bladder through the urethra.
The ureters are tubes of smooth muscle fiber which transfer the waste liquid from the kidneys as urine to the urinary bladder. The urine is moved with peristaltic movements, the contraction and relaxation of muscles, which force the urine away from the kidneys and into the bladder. The ureters also have ureterovesical valves, sphinter muscles, which ensure that the waste fluid will not go back into the kidney.
In case this does not work and urine backs up, or stands still, a kidney infection can be develop.
There are two of them, one for each kidney. They carry the deoxigenated blood that comes from all around the body through the Vena Cava and transport it into the kidneys to be removed from the waste products and urea that comes from the liver.
There are also two of them, one for each kidney. They carry the oxigenated blood that comes from the kidneys which filtered all the urea with toxic and in excess materials. Now it is ready to go to the heart and be pushed all around the body.
By: Trinidad Porretti & Anouk de Laferrere