AP Biology Chemistry of Life

Lipids or Fats

Made up of a glycerol molecule and three fatty acids molecules

Saturated fatty acids

Have no double bonds between carbonsTend to pack solidly at room temp.Are linked w/ cardiovascular diseaseAre commonly produced by animals

Unsaturated fatty acids

have some C=C (carbon double bonds) Tend to be liquid at room temp.Are commonly produced by plants

Lipid

Energy storage and protection of vitals organs are a function of a

Phospholipids

Make up cell membranesHave a polar head that includes a phosphate groupHave two fatty acid tails which are nonpolar

C,H,O,N

Make up 96 percent of living matter

Trace Elements

Required by an organism in only minute quantities

Compound

A substance consisting of two or more elements combined in a fixed ratio

Element

A substance that cannot be broken down to another substance by a chemical reaction

Matter

Fancy word for stuff; makes up everything; has mass and made of atoms

Atoms

Smallest unit of an element that still retains the property of an element

Protons

Positively charged particles found in the nucleus of the atom

Electrons

Negatively charged particles that are found in electron shells around the nucleus

Neutrons

Particles with no charge

Isotopes

Forms of an element with differing numbers of neutrons

Atomic number

The number of protons an element possesses

Mass number

Sum of an elements protons and neutrons

Chemical bonds

Interactions between the valence(combining power of an element) electrons of different atoms

Covalent bond

When valence electrons are shared by two atoms

Nonpolar covalent bond

When electrons are being shared equally between the two atoms

Polar covalent bond

When one atom has a greater electronegativity than the other, resulting in an unequal sharing of electrons

Ionic bonds

Two atoms attract valence electrons so unequally that the more electronegative atom steals the electron away from the less electronegative atom

Ion

Resulting charged atom after an ionic bond

Hydrogen bonds

Relatively weak bonds that form between partial positively charged hydrogen atom of one molecule and the strongly electronegative oxygen or nitrogen of another

Chemical reaction

Shows the reactants and an arrow to indicate their conversion into the products

Water molecules

1 oxygen and and 2 Hydrogen atoms; hydrogen bonds form between these.

Cohesion

The linking of like molecules

Adhesion

The clinging of one substance to another different substance

Transpiration

The movement of water molecules up the very thin xylem tubes and their evaporation from the stomata in plants; simple the evaporation of water from plants

Specific heat

The amount of heat required to raise or lower the temperature of a substance by 1*C

Hydrophilic

Water-soluble, include ionic compounds, polar molecules, and some proteins; water loving

Hydrophobic

Oils, nonpolar, and do not dissolve in water; water fearing

_pH

Measures the relative acidity and alkalinity of aqeneous solutions

Acids

Have an excess of H+ ions and a pH below 7.0

Bases

Have an excess of OH- ions and a pH above 7.0

Neutral

pH of 7; Pure water is

Buffers

Substances that minimize changes in pH

catabolic

reaction that breaks a compound down into smaller pieces

Characteristics of carbon

It has 4 valence electronsIt can form up to 4 covalent bonds(Single,Double,or Triple)It can form large moleculesThese molecules can be chains, ring shaped, or branched

Isomers

Molecules that have the same molecular formula but differ in their arrangement of these atoms

Polymer

Long chained molecules made of repeating subunits called monomers

Dehydration reactions

Create polymers from monomers. Two monomers are joined by removing one molecule of water

Hydrolysis

When water is added to split large molecules

Carbohydrates

Simple sugars and polymers1 carbon:2 hydrogen: 1 oxygen

Monosaccharides

The monomers of carbohydrates Ex. Glucose and Ribose

Polysaccharides

The polymers of monosaccharides Ex. Starch, cellulose, and glycogen

Starch

A storage polysaccharide found in plants

Glycogen

A storage polysaccharide found in animals, vertebrate muscle cells, and liver cells

Cellulose

polysaccharide; A major component of plant cell walls

Chitin

Polysaccharide; Found in the exoskeleton of insects and Arthropods and the cell walls of fungi

Anabolic

reaction that builds smaller molecules into larger compounds.

Steroids

Made up of four rings not that are fused together

Cholesterol

A steroid, common component of cell membranes

Estrogen and testosterone

Steroid hormones

Proteins

Polymers made up of amino acid monomers

Amino acids

Contain a central carbon bonded to a carboxyl group(COOH) at one end, an amino group(NH^2), a hydrogen atom, and an R group(variable)

Peptide bonds

Link amino acids, formed by dehydration synthesis between the amino and hydroxyl of adjacent monomers

The unique sequence of amino acids

Primary Structure (Part of Protein structure)

Coiling of the chain

Secondary Structure (Part of Protein Structure)

Coiling of the coil/ bending

Tertiary structure of proteins

Two or more chains together/ Layering

Quaternary structure of proteins

Alpha helix

A coiled shape/slinky

Beta pleated sheet

An accordion shape

Protein shape

Crucial to protein function

Denaturation

When a protein loses its shape and ability to function due to heat, change in pH, or some other disturbance

DNA (deoxyribonucleic acid)

The molecule of heredity Double strandedNucleotides are adenine, thymine, guanine, and cystonineA-T and C-G

RNA (ribonucleic acid)

Single strandedNucleotides are adenine, uracil, cystonine, and guanine

Nucleotides

Consist of nitrogenous base, pentose or 5-carbon sugar, Phosphate group

Nitrogenous base

Adenine, thymine, guanine, and cystonine in DNAAdenine, uracil, cystonine, and guanine in RNA

Pentose

Deoxyribose in DNA/ Ribose in RNA

cation

Positively charged atom

Anion

A negatively charged ion