Practice Questions

Glycoproteins and glycolipids on the surface form the glycocalyx, involved in cell adhesion.

Selective permeability ensures only specific molecules can pass, keeping internal homeostasis.

Membrane proteins can act as enzymes to catalyze reactions at the membrane surface.

Cholesterol restricts the lateral movement of phospholipids, thus decreasing fluidity at high temperatures.

Standard plasma membranes are approximately 7.5 nanometers (or 75 Angstroms) in width.

Maintaining concentration gradients against the electrochemical gradient necessitates active transport.

The "kinks" created by double bonds prevent tight packing, which lowers the melting point and increases fluidity.

Hormones and other signaling molecules bind to glycoprotein receptors on the cell surface.

Peripheral proteins are bound to the surface, not embedded, making them easier to isolate.

The phosphate group is ionized and hydrophilic, ensuring the "head" interacts with the aqueous environment.