Cell membrane transport

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Slide 43

Cotransport also uses the process of diffusion. In this case a molecule that is moving naturally into the cell through diffusion is used to drag another molecule into the cell. In this example glucose hitches a ride with sodium.

Slide 44

Receptor Proteins

These proteins are used in intercellular communication. In this animation you can see the a hormone binding to the receptor. This causes the receptor protein release a signal to perform some action.

Slide 45

Cotransport also uses the process of diffusion. In this case a molecule that is moving naturally into the cell through diffusion is used to drag another molecule into the cell. In this example glucose hitches a ride with sodium.

Slide 46

These are carrier proteins. They do not extend through the membrane. They bond and drag molecules through the bilipid layer and release them on the opposite side.

Slide 47

Vesicle-mediated transport

Vesicles and vacuoles that fuse with the cell membrane may be utilized to release or transport chemicals out of the cell or to allow them to enter a cell. Exocytosis is the term applied when transport is out of the cell.

Slide 48

Cell Membrane - Function – Endocytosis

The cell membrane can also engulf structures that are much too large to fit through the pores in the membrane proteins this process is known as endocytosis. In this process the membrane itself wraps around the particle and pinches off a vesicle inside the cell. In this animation an ameba engulfs a food particle.