Science - Trasportation in Plants

Only available on StudyMode
  • Download(s) : 25
  • Published : January 29, 2013
Open Document
Text Preview
Plants need water for photosynthesis but they take in water through their roots so they need to transport the water up the stem to the leaves. Water is taken in by the root hairs because there is a higher water potential in the soil than in the root hairs. Then osmosis occurs to move the water from a cell with high concentration of water to a cell with low concentration through the permeable membrane. Once the water has moved down the concentration gradient it reaches a vessel called a xylem. As water transpires form leaves it creates root pressure and water is forced up through the xylem. The cohesion of water allows them to bond together and aid in this process called the ‘transpiration pull’. Humans need water for every part of life. Like in plants water is absorbed in the walls of the small intestines by osmosis. In the small intestines there are structures called villi that help water absorb quicker into the bloodstream. Each villus is only one cell in thickness making it easier for water to diffuse through into the blood. Villi increase the surface area of the intestine and allow more blood to flow, reducing the concentration level of water in the blood. This allows osmosis to happen and gets water into the bloodstream. Unlike plants, animals have a circulatory system so our cell do not continue to absorb water and swell up because animals do not have cell walls like in a plant cell. (Freeman 2007) The circulatory system transports water to the correct cells to dispose of it through sweating and urination.

Processing water is more complicated in animals and people, although it's also similar in a lot of ways. Water that you consume is absorbed in the upper small intestine through osmosis. It enters thebloodstream and is transported all over the body. Unlike plant cells, however, animal cells do not have cell walls. This is why animals have circulatory systems -- otherwise, our cells would absorb water and salt until they swelled. Our circulatory...
tracking img