1
1
Cell Membrane-Structure and
Function
BIO 250
Living things are composed of cells
and cell products (extracellular)
Cells are the basic unit of structure
They are the basic unit of function
They vary in size, shape and function
Shape related to function
– RBC shape gives large surface area for gas
exchange
– Nerve cell (neuron) has long threadlike fiber to
communicate over long distance
Adult human has about 75 trillion cells.
Cell membrane
Separates outside from inside cell
Selectively permeable
Composed primarily of phospholipids and
p
roteins with some carbohydrates,
cholesterol and ions
Plays a role in intercellular communication
