A cell's plasma membrane demarcates the cell's borders and determines the nature of its interaction with the environment. Cells exclude certain ...

Plasma membranes have integral transmembrane proteins involved in facilitated transport. These proteins are collectively referred to as transport ...

Lipids are an essential component of all biological membranes. The average lipid content in mammalian membranes is 50%, though it can be as low as 20% in ...

The plasma membrane is a dynamic barrier composed of lipids, proteins, and carbohydrates. It is the epicenter of many cellular processes required for cell ...

The glycocalyx is a carbohydrate-rich, fuzzy-appearing layer on the outer surface of the cell membrane. It is highly hydrophilic, because of this it ...

The transport of solutes across the cell membrane is essential for metabolic processes, like maintaining cell size and volume, generating the action ...

Diffusion is a type of passive transport. In passive transport, a substance tends to move from an area of high concentration to an area of low ...

The chemical and physical properties of plasma membranes cause them to be selectively permeable. Since plasma membranes have both hydrophobic and ...

Ion channels are specialized proteins on the plasma membrane that allow charged ions to pass down their electrochemical gradient. Their main function is ...

Osmosis is the movement of free water molecules through a semipermeable membrane.  The water's concentration gradient across the membrane is ...

Tonicity describes the amount of solute in a solution. The measure of the tonicity of a solution, or the total amount of solutes dissolved in a specific ...

In contrast to passive transport, active transport involves a substance being moved through membranes in a direction against its concentration or ...

One example of how cells use the energy contained in electrochemical gradients is demonstrated by glucose transport into cells. The ion vital to this ...

The ER, Golgi apparatus, endosomes, and lysosomes work in tandem to modify, sort, and package proteins and lipids. An integrated membrane trafficking ...

Receptor-mediated endocytosis is when bulk amounts of specific molecules are imported into a cell after binding to cell surface receptors. The molecules ...