Cell Size Surface Area- Volume
Cell Biology- Osmosis, Cell Size and Diffusion and Enzymes
1.0 INTRODUCTION
Cells are the basic building blocks of all living things. They provide structure for the body, take in nutrients from the food, convert those nutrients into energy, and carry out specialized functions. Cells also contain the body’s genetic material and can make copies of themselves. A cell is also a metabolic compartment where many different chemical reaction occur. There are two types of cells, eukaryotic and prokaryotic. Prokaryotic cells are usually unicellular, while eukaryotic cells can either exist as a single celled organism or be found in multicellular organisms. The unicellular and multicellular organisms are linked to cell size and surface area to volume ratio. The experiment for cell size and diffusion was set to see how and how much water can go to the cells. This movement of water is called Osmosis. Osmosis is the movement of water molecules from an area of low concentration (lots of water) to an area of high concentration (little water) through a semi permeable membrane, demonstrated in ‘figure 1’. A semi permeable membrane is a membrane that only lets selected molecules to pass through it. In a plant water is taken into the roots by the process of Osmosis. This is because the cells inside the roots have a higher concentration of solutes than the soil outside the roots, water diffuses from an area on high concentration to an area of low concentration. When a large volume of water enters the cell, it swells causing the membrane to push against the cell wall which is called turgor pressure. When the water moves out of the cell, the membrane shrinks away from the cell wall and becomes a loose cell, plasmolysis. This causes the plant to wilt, as the cells can no longer provide support for the leaves.
Figure1. How Osmosis works
As already known, proteins in our cells do many things. One of the most important things they do is act as an enzyme. An enzyme is a biological
1.0 INTRODUCTION
Cells are the basic building blocks of all living things. They provide structure for the body, take in nutrients from the food, convert those nutrients into energy, and carry out specialized functions. Cells also contain the body’s genetic material and can make copies of themselves. A cell is also a metabolic compartment where many different chemical reaction occur. There are two types of cells, eukaryotic and prokaryotic. Prokaryotic cells are usually unicellular, while eukaryotic cells can either exist as a single celled organism or be found in multicellular organisms. The unicellular and multicellular organisms are linked to cell size and surface area to volume ratio. The experiment for cell size and diffusion was set to see how and how much water can go to the cells. This movement of water is called Osmosis. Osmosis is the movement of water molecules from an area of low concentration (lots of water) to an area of high concentration (little water) through a semi permeable membrane, demonstrated in ‘figure 1’. A semi permeable membrane is a membrane that only lets selected molecules to pass through it. In a plant water is taken into the roots by the process of Osmosis. This is because the cells inside the roots have a higher concentration of solutes than the soil outside the roots, water diffuses from an area on high concentration to an area of low concentration. When a large volume of water enters the cell, it swells causing the membrane to push against the cell wall which is called turgor pressure. When the water moves out of the cell, the membrane shrinks away from the cell wall and becomes a loose cell, plasmolysis. This causes the plant to wilt, as the cells can no longer provide support for the leaves.
Figure1. How Osmosis works
As already known, proteins in our cells do many things. One of the most important things they do is act as an enzyme. An enzyme is a biological
Bibliography: John Kyrk, 2013, Cell Biology Animation, Batavia, http://www.johnkyrk.com/ Flinn, 2013, Cell Size and Diffusion, http://www.flinnsci.com/teacher-resources/teacher-resource-videos/see-it-in-action-videos/biology/cell-size-and-diffusion,-fb1638/ Regina Bailey, Diffusion and Passive Transport, http://biology.about.com/od/cellularprocesses/ss/diffusion_3.htm CliffsNotes, Enzymes, http://www.cliffsnotes.com/study_guide/Enzymes.topicArticleId-8741,articleId-8592.html Huxley L, Walter M,1998, Biology, Oxford, New York