Cell Membrane & Osmosis/Diffusion

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​ORHS BIOLOGY - ZANDER

Intro to Cell Transport​

​The cell membrane is also know as the plasma membrane.

• It separates the living cell from its nonliving surroundings.

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​This double-layered, thin barrier, controls traffic into and out of the cell and is known as the lipid bilayer.

• bi = two ​

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​Like many other membranes, the plasma membrane is selectively permeable (semi permeable)

• allowing small uncharged substances to cross more easily than larger charged substances.

• ​Consists of hydrophobic (water fearing) tails and hydrophilic (water loving) heads.

• Proteins serve as support and transport molecules.

• Carbohydrates help in cell to cell communication and act as radio towers.

The cell membrane is a semi-permeable membrane - it selects what enters and exits and cell (small uncharged molecules can easily exit and enter the cell).

• Movement across the cell membrane can be broken down into two categories:

1.Passive Transport- movement of materials into and out of the cell that does not require energy

• Ex: diffusion, osmosis, and facilitated diffusion

The cell membrane is a semi-permeable membrane - it selects what enters and exits and cell (small uncharged molecules can easily exit and enter the cell).

• Movement across the cell membrane can be broken down into two categories:

1.Passive Transport- movement of materials into and out of the cell that does not require energy

• Ex: diffusion, osmosis, and facilitated diffusion