Human body systems

The skeletal system

There are so many different systems that function in our body such as skeletal system, muscular system, digestive system, etc. Each of these systems helps us live our everyday lives. They are crucial in maintaining our health. On this post, I will discuss three: the skeletal system, excretory system, and the digestive system.

The picture above is a diagram of the skeletal system. Functions of the skeletal system include support, movement, protection, blood cell production, calcium storage, and endocrine regulation. Bones have a dense and tough outer layer, and new cells are constantly being produced for blood in the middle of some bones. One interesting fact is that teeth, although it is part of the skeletal system, are not bones. All the other parts that constitute the skeletal system are bones.

The skeletal system can be infected by several diseases, including osteoporosis and osteomalacia. X-Rays, MRIs, bone density tests, and arthroscopy can be used to detect those kinds of diseases.

 

The excretory system

The excretory system consists of the kidney, ureter, bladder, and urethra. In terms of the kidney, there are three important terms: renal cortex, medulla, and the renal pelvis. The renal cortex is the outer layer of the kidney, and the medulla is the inner layer. The renal pelvis takes urine away from the kidney through the ureter.

Blood from the heart enters the kidneys through renal arteries, and it splits into several arterioles. The arterioles go to the Bowman’s Capsules of nephrons, and here the wastes are taken out of the blood by pressure filtration. Peritubular capillaries surround the nephron so substances can be taken in and out of the blood.

 

The digestive system

The digestive system constitutes of the mouth, throat, esophagus, stomach, small intestine, and large intestine. First, food is chopped into small pieces by teeth, and moistened by saliva. The throat passes chewed food from the mouth to the esophagus. Then the esophagus carries food to the stomach, and in the stomach, food is stored and digested with digestive enzymes. The small intestine extracts 90% of the nutrients from food, and finally, the large intestine breaks down wastes to extract small amounts of nutrients.

 

Works cited :

crashcourse. “The Skeletal System: It’s ALIVE! – CrashCourse Biology #30.” YouTube, YouTube, 20 Aug. 2012, http://www.youtube.com/watch?v=RW46rQKWa-g.

“Advertisement.” Excretory System,excretorysystem.organsofthebody.com/

crashcourse. “The Excretory System: From Your Heart to the Toilet – CrashCourse Biology #29.” YouTube, YouTube, 13 Aug. 2012, http://www.youtube.com/watch?v=WtrYotjYvtU.

“Advertisement.” Digestive System, digestivesystem.organsofthebody.com/.