Cell Structure and Function
Science

The transport of materials across the cell membrane by transport proteins
Facilitated diffusion
The transport of materials across the cell membrane by transport proteins. Facilitated diffusion. Facilitated diffusion is a process where transport proteins help move substances across a cell membrane without using energy.

A model of the cell membrane showing molecules in constant motion
Fluid mosaic model
A model of the cell membrane showing molecules in constant motion. Fluid mosaic model. This model describes the cell membrane as a flexible layer with proteins embedded in or attached to a sea of lipids, allowing movement and fluidity.

The cell structure that packages materials for transport within and out of cell
Golgi body
The cell structure that packages materials for transport within and out of the cell is the Golgi body. The Golgi body is like the cell's post office, preparing and sending proteins and other materials to their destinations.

A solution with a higher solute concentration than that of cells in that solution
Hypertonic solution
A solution with a higher solute concentration than that of cells in that solution. Hypertonic solution. In simple terms, a hypertonic solution will cause cells to lose water and shrink because it has more dissolved substances than inside the cells.

A solution with the same solute concentration as the cells it contains
Isotonic solution
A solution with the same solute concentration as the cells it contains. Isotonic solution. An isotonic solution is one where the cell and the surrounding solution have equal concentrations of solutes, preventing water movement that would cause the cell to shrink or swell.

The ability of cell membranes to allow some, but not all, substances to pass through
Selective permeability
The ability of cell membranes to allow some, but not all, substances to pass through selective permeability. Selective permeability means that a cell membrane controls which substances can enter or leave the cell.