ap bio unit 1

amino acid

the building blocks of proteins

amphipathic

a molecule possessing both a hydrophobic and hydrophilic portion (ex. phospholipids and fatty acids)

carbohydrates

organic molecules consisting only of carbon, hydrogen, and oxygen that serve as structural components in cells and as energy sources (CH₂O)

carbon

atom around which life is based, mainly due to its ability to form four stable covalent bonds and long chained molecules

denaturation

the loss of a protein’s three dimensional functional structure

disaccharide

a double sugar molecule used as energy sources and building blocks of larger molecules (ex. maltose, sucrose, lactose)

ester bond

the bond between an alcohol and an acid (ex. glycerol and fatty acid)

fibrous proteins

these proteins are very tough and often have a structural role in cells

globular proteins

these proteins are water soluble and have catalytic and regulatory roles in cells

hydrogen bond

the attractive interaction of a hydrogen atom with an electronegative atom, such as nitrogen, oxygen, or fluorine

inorganic ion

a charged molecule that does not contain carbon

lipids

a class of organic compounds with an oily, greasy, or waxy consistency. important as energy storage molecules and as components of cellular membranes (CHOP)

macromolecule

a very large, complex molecule often made up of smaller units (ex. protein or polysaccharides)

monomer

a molecule made up of a single unit

monosaccharides

carbohydrate monomers (ex. glucose, fructose, galactose)

nucleic acids

polynucleotide molecules that occur in two forms - DNA and RNA (CHNOP)

nucleotide

molecules comprising a purine and pyrimidine bonded with a pentose sugar (ribose or deoxyribose) and a phosphate group

organic molecule

a molecule that contains carbon

peptide bond

covalent bond formed when a carboxyl group and an amine group react and release a molecule of water. in biological systems this leads to the formation of proteins

phospholipids

a class of amphipathic lipids, they are a major component of all cell membranes as they can form lipid bilayers

polar

a molecule in which the opposite ends are oppositely charged

polysaccharides

complex carbohydrates with structural and energy storage roles in cells, (ex. cellulose, starch, glycogen, chitin)

proteins

organic compounds, usually linear polymers, made of amino acids linked together by peptide bonds (CHNOS)

water

polar molecule consisting of two hydrogen atoms and one oxygen atom (H₂O)

1st degree organization

amino acids form peptide bonds and create a polypeptide

2nd degree organization

hydrogen bonding causing either an alpha helix or a beta pleated sheet

3rd degree organization

reinforced by interactions of amino acids - forms peptide bonds, hydrogen bonds, ionic bonds, disulfide bridges, R group interactions, hydrophobic interactions

4th degree organization

association between 2 or more polypeptide chains, globular in shape

glycosidic linkage

in carbohydrates, connecting rings with an “O”

what are monomers of enzymes?

amino acids are monomers of enzymes

a higher (basic/alkaline) pH means

[H⁺]<[OH^-]

a lower (acidic) pH means

[H⁺]>[OH^-]

a neutral (7) pH means

[H⁺]=[OH^-]

a bond between carbon and nitrogen is

a peptide bond

bonds in DNA

1. phosphodiester bonds

2. hydrogen bonds

double helix

two polynucleotides that wind around an imaginary axis, seen in structure of DNA

antiparallel

two-sugar phosphate backbones that run in opposite directions from each other like a divided highway, measured 5’ to 3’ which align to the opposite side’s 3’ to 5’

RNA and DNA difference in diagrams

RNA - OH, adenine & uracil, cytosine & guanine
DNA - H, adenine & thymine, cytosine & guanine