Chemistry and Cell Biology

Atom

The smallest unit of matter that retains its orginal properties.

Element

A substance that cannot be broken into simpler substances by chemical means; consists of one or more atoms with the same atomic number.

Molecule

Two or more joined by a chemical bond.

Compunds

something composed of two or more elements

Solution

Consists of a solid, liquid, gas mixed with a liquid (mostly water)

Solute

The substance that is dissolved

Solvent

The substance that has a higher amounts in a solution

Colloid

Two distinct components; particles small and not visible

Suspension

Particles are large and visible; liquid mixed with solid

Emulsion

Tiny lipid droplets each coated with bile salts

Covalent Bond

The sharing of electrons between 2 atoms

Ionic Bond

transfer of electrons; joined together due to opposite charges

Hydrogen Bond

Weak attraction between partially positive hydrogen atoms of one compound or functional group and partially negative atoms of another compound or functional group.

Non polar bond

electrons are shared equally and there is no partial charges

Polar covalent bond

A bond where electrons spend more time around the more electronegative atom; dipole is formed

Dehydration Synthesis

Definition: Anabolic reaction where two monomers are linked together by a covalent bond.

Products: polymer compound and a molecule of water

Hydrolysis Reaction

Definition: A molecule of water is added to a polymer, splitting it into component monomers

Enzyme

a biological catalyst; speeds up a reaction without changing its products or reactants

Role of ATP in a cell…

provides the energy needed for many essential processes in organisms and cells

What makes properties of water possible?

Hydrogen bonds

Important Properties of Water

1. Water absorbs heat without changing significantly in temperature itself
2. Water carries heat with it when it changes from liquid to gas
3. Water cushions and protects body’s structures
4. Water acts as a lubricant between two adjacent surfaces

Primary Structure

Amino acid sequence of its polypeptide which is held by covalent peptide bonds

Secondary Structure

Amino acids of the protein interact by H binds to form alpha helix or a beta-pleated sheet.

Tertiary Structure

Interactions between R groups help to determine the shape of the protein assumed after its folding. 

Quaternary Structure

The assembly of two or more polypeptide chains into the functional protein. Not every protein has a quaternary structure. 

Hypertonic

Causes a cell to lose water.Drives osmosis which means that that extracellular fluid loses water as it leaves the cell and enters ECF. This can cause the cell to shrivel and possibly die.

Isotonic

Water enters and leaves the cell at the same rate; no gain or loss of water overtime; volume remains the same. 

Hypotonic

Causes the cell to gain water. Has a lower ability to cause osmosis, so the cytosol will move water from the ECF into the cytosol. This can cause the cell to swell and rupture. 

Exocytosis

Releases of a substance from the cell through the exocytic transport vesicle; ATP required

Phagocytosis

“Cell eating” bringing large molecules or particles into the cell through a phagosome; ATP required

Pinocytosis

“Cell drinking” brings substances in the ECF into the cell through the transport vesicle formed from a protein-coated pit; ATP required

Endocytosis

Bringing a specific substance into a transport vesicle using receptors on the plasma membrane; ATP required

Monomer

basic building block