1.Describe the component parts of a cell and how cell interactions occur.Some of these interactions are meant for big molecules that enter and exit the cell called, endocytosis (entering the cell) and exocytosis (exiting the cell). For smaller particles like amino acids, water, ions and other solutes there are different types of direct contact between the cells called gap junctions. During exocytosis, the phospholipid bilayer of the cell membrane surrounds the waste proteins, creating a bubble-like structure called a vesicle. Vesicles are frequently used in the cell for transportation of molecules across the cell membrane. Waste Proteins: waste products being ejected out of the cell, instead of proteins being incorporated into the cell membrane. Once, the vesicle has enclosed the waste proteins on the inside of the cell, it moves towards the cell membrane. The vesicle merges with the cell membrane, opening the bubble-like structure and ejecting the contents in the environment surrounding the cell.Exocytosis is also used to integrate new proteins into the cell membrane. In this process, the new proteinis formed inside the cell, and migrates to phospholipid bilayer of the vesicle. The vesicle, containing the new protein as a part of the phospholipid bilayer, fuses with the cell membrane. This allows the protein to be directly integrated into the cell membrane when the vesicle, in the same way as with waste proteins, fuses and opens with the cell membrane.Endocytosis brings molecules into the cell. These molecules are important for the survival of the cell, such as glucose. There are three different styles of endocytosis: 1) phagocytosis: engulfs a molecule in order to move it to the interior of the cell, binding to specific receptors on the surface of the cell membrane, triggering the cell membrane to reshape, surrounding the molecule.
You've reached the end of your free preview.
Want to read all 4 pages?
- Winter '14