The part of the brain that loses volume when gyri narrow and the sulci widen is called the

Phospholipid bilayer - Double layered sheet that gives the cell membrane a strong flexible barrier.

Selectively permeable- Some substances can pass through and others cannot.

Extracellular fluid - Solution found on the outside of a cell .

Intracellular fluid - Solution found on the inside of the cell.

Solution - A mixture that is not easily separated, made up of a solvent and solute

Solute - Substance that is bearing disolved , ex:salt.

Solvent - Substance doing the dissolving , ex :water

Homeostasis - Ability to maintain a steady state.

Equilibrium - Steady state balanced .

Hydrophobic - Water “fearing”

Hydrophilic - Water “loving”

Phospholipid - The main component of the cell membrane, composed of a hydrophilic head and hydrophobic tails.

Concentration gradient - A difference in the number of molecules across a membrane

Explanation: