Unit 5, P4, M1, D1 Essay example

775 Words Mar 3rd, 2015 4 Pages
Energy keeps all living organisms alive, as they need a continual supply of energy to function in order to survive. Some of these processes are continuous such as, metabolism, which is the chemical reactions which occur in the body, these occur by using or releasing energy from chemical substances. Another continuous process which use energy is the transporting of molecules in order for them to break down, and to build new ones. The breakdown of large molecules into their simpler forms to release energy is known as catabolism, for example, when glucose is used in a cell to release energy. And the opposite reaction, is called anabolism. This is when energy is used to build complex structures from simple cells, for example, tissue growth and …show more content…
Oxygen + Glucose = Energy + Carbon Dioxide + Water
First the air that’s breathed in travels down the trachea, into the lungs, through the bronchioles and into tiny air sacs called alveoli. The oxygen in the alveoli diffuses into the capillaries, where there’s a lower concentration of oxygen. The thin walls of the capillaries allow the oxygen to diffuse through into the blood. The circulatory system then carries the blood around the body, supplying cells with the oxygen required for energy; allowing them to function. Glucose is also needed, which comes from the digestive system. Glucose is made from the sugary or starchy foods consumed. It start off in the mouth where the salivary glands produce saliva, which contains amylase which breaks down the sugars and starch. It then travels to the stomach, where it’s mixed with other enzymes and fluids, becoming a mixture known as chyme. Chyme, then travels to the small intestine where there are tiny, finger-like structures called villi on the surface walls of the intestine. Villi, are one cell thick making it easy to absorb particles, such as glucose, into the blood from the chyme which is passing through the small intestine. Once in the bloodstream, the circulatory system transports the glucose to cells to be used for energy.

More about Unit 5, P4, M1, D1 Essay example