Cell Membrane in Biological Systems

These flashcards cover key vocabulary and concepts related to the structure and function of cell membranes as discussed in Biological Systems - Lecture 2.2.

Phospholipid bilayer

A double layer of phospholipids that forms the core of a cell membrane, containing hydrophilic and hydrophobic regions.

Fluid mosaic model

Describes the structure of cell membranes as a mosaic of various components including phospholipids, proteins, and carbohydrates that move freely.

Diffusion

The process by which particles spread out from an area of high concentration to an area of low concentration.

Osmosis

The diffusion of water across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Passive transport

The movement of substances across a cell membrane without the use of energy, such as diffusion and facilitated diffusion.

Active transport

The movement of substances across a cell membrane against their concentration gradient, requiring energy.

Aquaporins

Integral membrane proteins that facilitate the transport of water across the cell membrane.

Exocytosis

The process where a cell expels large molecules by enclosing them in a vesicle that fuses with the plasma membrane.

Endocytosis

The process by which cells internalize substances by engulfing them in a vesicle.

Hypertonic solution

A solution with a higher concentration of solute compared to the cytoplasm, causing cells to lose water and possibly shrink.

Hypotonic solution

A solution with a lower concentration of solute compared to the cytoplasm, leading to water influx, which can cause cells to swell and burst.