Cell Membranes Lecture Notes

This set of flashcards covers key vocabulary and concepts related to cell membranes, their structure, and functions as outlined in the lecture notes.

Hydrophilic

Water-loving; associated with carbohydrates.

Hydrophobic

Water-fearing; associated with lipids (fats).

Phospholipid

A lipid with a hydrophilic region (head) and hydrophobic region (tails) that forms cell membranes.

Glycolipid

A lipid with carbohydrate(s) attached, important for self-identification and cell function.

Membrane Protein

Proteins that allow transport, signaling, adhesion, identification, and enzymatic activity across the membrane.

Integral Protein

Membrane proteins that span the entire lipid bilayer.

Peripheral Protein

Membrane proteins that are attached to the surface of the membrane.

Glycocalyx

A layer of carbohydrates on the extracellular face of the membrane; important for cell adhesion and immune function.

Microvilli

Fingerlike projections that increase the surface area of cells.

Cilia

Microscopic structures that facilitate coordinated movement.

Diffusion

The movement of solutes from high concentration to low concentration.

Osmosis

The diffusion of water across a membrane from low solute to high solute concentration.

Isotonic

Solutions with the same concentration of solutes.

Hypertonic

Solutions with a higher concentration of solutes compared to another solution.

Hypotonic

Solutions with a lower concentration of solutes compared to another solution.

Aquaporins

Channels that increase water permeability in cell membranes.

Endocytosis

Process of bringing materials into the cell using membrane-bound vesicles.

Exocytosis

Process of moving materials out of the cell using vesicles.

Phagocytosis

Endocytosis of large particles by specialized cells.

Pinocytosis

Endocytosis of small amounts of extracellular fluid.

Receptor-mediated Endocytosis

Endocytosis initiated by receptors detecting target molecules.

Sodium/Potassium ATPase

Pump that maintains sodium and potassium gradients across the membrane.

Primary Active Transport

Transport that directly uses ATP to move substances against their concentration gradient.

Secondary Active Transport

Transport that uses an established ion gradient for energy to move substances.

Facilitated Diffusion

Passive transport that requires protein channels or carriers for molecules that cannot cross the lipid bilayer directly.

Channel Protein

Proteins that allow specific solutes to pass through the membrane when open.

Gated Channel

Channel proteins that can be opened or closed to regulate solute passage.

Concentration Gradient

A difference in the concentration of a substance across a space.

Transport Maximum (Tm)

The maximum rate at which transport proteins can move solutes across the membrane.

Carriers vs. Channels

Carriers are slower and can transport larger solutes; channels are fast and transport down the gradient.

Passive Transport

Movement of solutes down their concentration gradient without the use of energy.

Active Transport

Movement of solutes against their concentration gradient that requires energy.