Water Chemistry and Cell Membrane Transport: Key Concepts for Biology

Water

1 oxygen atom, 2 hydrogen atom

Water Molecular formula

H2O

Covalent Bond

Bond between hydrogen and oxygen within a water molecule

Polar Molecule

because electrons spend more time near oxygen making the oxygen side more negative and the hydrogen side more positive.

Hydrogen Bonds

bond between a hydrogen and oxygen on TWO DIFFERENT water molecules

Adhesion

Attraction between molecules of different substances

Cohesion

Attraction between molecules of the same substances

Surface Tension

A measure of how difficult it is to stretch or break the surface of a liquid

Capillary Action

the combined force of attraction among water molecules and with the molecules of surrounding materials

Water states of matter

solid, liquid, gas

Density of Water

Due to hydrogen bonds that allow liquid water to expand as it becomes ice.

High Heat Capacity

Engergy needed to change the temperature of a substance

High heat of vaporization

engergy need to change a substance from a liquid to a gas

Universal Solvent

Water dissolves other polar molecules and substances with a change

Cell Membranes

-Seperate the inside of the cell from the outside of the cell

-Responsible for moving molecules in and out of the cell

-The cell membrane is made of a phospholipid bilayer

Semi Permiable

Only lets certain molecules across

Active Transport

Energy-requiring process that moves material across a cell membrane against a concentration difference

Passive Transport

Requires NO energy, Movement of molecules from high to low concentration, Moves with the concentration gradient

Osmosis

Movement of water across membrane from an area with high solute concentration to an area with low solute concentration

Diffusion

Molecules moving across a membrane from an area of high concentration to low concentration

Facillitated Diffusion

Molecules moving across a membrane from an area of high concentration to low concentration with the help of embeded proteins

Hypertonic

when comparing two solutions, the solution with the greater concentration of solutes

Hypotonic

Having a lower concentration of solute than another solution

Hydrophilic

Attracted to water

Hydrophobic

water hating

Lipid Structure

composed of 2 parts (1 hydrophilic head, 1 hydrophobic tail)

Lipid properties

Nonpolar, make up cell membrane

sugar properties

Polar, Hydrophilic, carbon based