Biology unit 4 (cell membrane components)

Lipid Bilayer

two sheets of phosphate + lipids

Each phospholipid is made of a polar phosphate "head" and 2 nonpolar lipid (fatty acid) "tails."

The head is hydrophilic (water-loving) and the tail is hydrophobic (water-fearing).

Channel Proteins

A type of integral protein- have a channel for water/solute to pass easily - specific to molecules

Carrier Proteins

A type of integral protein- shape of the solute matches the shape of the protein - specific to molecules

Integral Proteins

embedded in the membrane and can extend across the entire cell membrane - may have a channel for passage of molecules

Peripheral Proteins

located on the interior and exterior surfaces of the cell membrane - can work with integral proteins or can strengthen the structure of the cell

Glycoproteins

A type of integral or peripheral protein where a carbohydrate chain is attached to a protein in the cell membrane- helps a cell recognize other cells around it by using the carbohydrate chains

Wrong chain triggers body to reject the cell

Receptor Proteins

A type of integral protein that have a binding site on the outside of the cell

Chemicals can bind to this site and stimulate a cellular response

Ion Pump

A type of integral protein- can change shape and pump ions from one side of the membrane to the other

Moves ion against the concentration gradient (low to high concentration)

Requires energy

Enzyme

Can be integral or peripheral proteins that help to catalyze cellular reactions

Glycolipid

carbohydrate chain attached to lipid in cell membrane

A type of lipid that helps a cell recognize other cells around it by using the carbohydrate chains

Wrong chain triggers body to reject the cell

Cholesterol

Type of lipid

Makes the membrane less flexible and less permeable- strengthens the cell membrane