Cell Membrane

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Submitted By angelstar
Words 506
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The aim of this experiment is to investigate the influence of various alcohols and temperature on the permeability of beetroot cell membrane. The different types of alcohol will include ethanol, methanol, propanol, butanol and the tissue from the beetroot will be exposed different salt concentrations (0%, 5% ,10% and 20%) . The stress affecting the membrane’s permeability will be assessed by the amount of leakage of pigment caused.
‘Homeostasis the ability of the body or a cell to seek and maintain a condition of equilibrium or stability within its internal environment when dealing with external changes’ (Biology, 2014). Organelle membranes and the plasma membrane are selectively permeable, allowing water to pass through freely, but regulating the movement of solutes. The function of a cell membrane is to transport and allow certain substances into the cell, while keeping other substances out. Surrounding the cytoplasm of a cell, the cell membrane (plasma membrane) is a thin semi-permeable membrane (Bailey, 2014) consisting mostly of lipids and proteins and composed up of a phospholipid bilayer. This contributes to the selectively permeable nature of the membrane.
70% of proteins contribute to the cell membrane, allowing communication outside and inside the cell. The phospholipids arrange themselves so that hydrophobic tails are shielded from the surrounding water exposing the hydrophilic heads to the water. While small molecules and non-charged ions cross freely, big charged oins cannot simply cross. They travel though either by passive or active transport.
Active transport requires energy from food, obtained by the cell, to move molecules through the membrane. However, unlike active transport passive occurs spontaneously requiring no energy required from (ATP). Diffusion is a form of passive movement. It is the tendency of molecules to spread into available…...

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