Cell Transport Mechanisms and Permeability
CELL TRANSPORT MECHANISMS AND PERMEABILITY
Zack Johnson
Human Anatomy & Physiology Lab 2101
Instructor: Alan Byboth, M.S.
10/4/12
Abstract- The cell is invaluable building block of all biological life on this planet, and one of its most important and unique characteristics is its ability to be selectively permeable with its plasma membrane. This outer membrane’s sophisticated mechanisms of transport through its bilayer are vital in maintaining homeostasis in the cell and the entire body. To further understand these mechanisms, which can be further described as passive and active transport, five experiments were conducted. These tests were done over simple diffusion, facilitated diffusion, osmosis, filtration, and active transport by changing and observing different variables and how they affect transport through the membrane. Obtained was the understanding of the changing of the molecular weight cut off in a membrane, and how it does not play a part directly in changing the rate of diffusion, but instead determined if diffusion was accomplishable at all. Knowledge on the size of molecules in relation to how they behave through these mechanisms was also learned. The smaller solutes tend to be consistently more successful in all forms of transport. To understand the cell transport is to, to an extent, understand the cell and indirectly the human race.
Introduction-
All living cells possess the ability to be selectively permeable. In other words they are able to control what substances and molecules enter and leave the cell. This monitoring, however, is in many ways much more complex than a simple wall and gate concept, but in some forms it does share likeness to it. All of this inward and outward traffic is controlled by the Plasma Membrane. The Plasma Membrane is the outermost layer of the cell, and consists mostly of a phospholipid bilayer, but also houses some proteins and other substances to aid in the crossing through the membrane. The
Zack Johnson
Human Anatomy & Physiology Lab 2101
Instructor: Alan Byboth, M.S.
10/4/12
Abstract- The cell is invaluable building block of all biological life on this planet, and one of its most important and unique characteristics is its ability to be selectively permeable with its plasma membrane. This outer membrane’s sophisticated mechanisms of transport through its bilayer are vital in maintaining homeostasis in the cell and the entire body. To further understand these mechanisms, which can be further described as passive and active transport, five experiments were conducted. These tests were done over simple diffusion, facilitated diffusion, osmosis, filtration, and active transport by changing and observing different variables and how they affect transport through the membrane. Obtained was the understanding of the changing of the molecular weight cut off in a membrane, and how it does not play a part directly in changing the rate of diffusion, but instead determined if diffusion was accomplishable at all. Knowledge on the size of molecules in relation to how they behave through these mechanisms was also learned. The smaller solutes tend to be consistently more successful in all forms of transport. To understand the cell transport is to, to an extent, understand the cell and indirectly the human race.
Introduction-
All living cells possess the ability to be selectively permeable. In other words they are able to control what substances and molecules enter and leave the cell. This monitoring, however, is in many ways much more complex than a simple wall and gate concept, but in some forms it does share likeness to it. All of this inward and outward traffic is controlled by the Plasma Membrane. The Plasma Membrane is the outermost layer of the cell, and consists mostly of a phospholipid bilayer, but also houses some proteins and other substances to aid in the crossing through the membrane. The
Cited: Guyton, A.C., Hall, J.E., 1996. Transport of Ions and Molecules through the Cell Membrane. Textbook of Medical Physiology. 43-54 Reece, J.B., Urry, L.A., Cain, M.L., Wasserman, S.A., Minorsky, P.V., Jackson, R.B., 2011. Membrane Structure and Function. Campbell Biology. 131-138, 960 Seifter, J., Ratner, A., Sloane, D., 2005. Membrane Transport. Concepts of Medical Physiology. 16-19