AP Bio- Unit 1

Covalent Bonds

Sharing a pair of valence electrons
Strong bond
Ex: Water atom

Cation

+

Anion

-

Ionic bonds

Transfer of electrons
Strength relies on environment (in the middle)
Ex: Salts

Hydrogen bonds

When a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule
Very weak
Ex: Only hydrogen is involved

Properties of water

-cohesive behavior
-ability to moderate temperature
-doesn't change temperature too quickly
-expansion upon freezing
-versatility as a solvent

Lower than 7 pH

Acid

Higher than 7 pH

Basic

pH scale reason

The PH of an atom is the measure (the percent) of the amount of hydrogen or hydronium within the atom (chance)
(acids have more hydrogen, basics less)

Adhesion

An attraction between molecules of different substances

Cohesion

Attraction between molecules of the same substance

Polar molecule

Molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end

Hydrophilic

Affinity for water (polar)

Hydrophobic

Non-affinity for water (non-polar)

Surface tension

Breaking the hydrogen bonds

Solvent

Doing the dissolving

Solute

What's being dissolved

Non-polar dissolves

Non-polar

Polar dissolves

Polar

A solvent and a solute make a

Solution

Monomers

Building blocks of polymers

Polymers

Made up of monomers

Condensation reaction

A chemical reaction in which two or more molecules combine to produce water or another simple molecule

Dehydration reaction

A chemical reaction in which molecules combine by removing water

Hydrolysis reaction

A chemical reaction that breaks apart a larger molecule by adding a molecule of water

Monosaccharides

Single sugar molecules (short term energy)

Disaccharides

Carbohydrates that are made up of two monosaccharides

Polysaccharides

Carbohydrates that are made up of more than two monosaccharides

Carbohydrates

Monosaccharides, disaccharides, polysaccharides

Lipids

Triglycerides, phospholipids, steroids

Carbon

Backbone of all living things, has four valence (and only needs four) making it neutral. Will make double, triple, quadruple bonds

Hydrocarbons

Molecules consisting of only carbon and hydrogen (fuel ex.)

Buffers

Substances that minimize changes in concentrations of H+ and OH- in a solution. Used all the time to resist changes that can be possibly fatal.

Substrate

What an enzyme acts on

Enzymes are ___ in a reaction

Not consumed

Activation energy and enzymes

Enzymes are the first push that the reaction needs. Enzymes hasten reactions that would occur naturally.

Active site of an enzyme

The region of an enzyme that attaches to a substrate

Temp and pH affect enzymes

Depends per enzyme- each has an optimal condition

Competitive inhibitors

Reduce the productivity of enzymes by blocking substrates from entering active sites

Non-competitive inhibitors

Bind to another part of an enzyme, causing the enzyme to change shape and making the active site less effective

Exergonic

Energy releasing

Endergonic

Energy taking

Activation energy

Energy needed to get something going

Chemical energy

Potential energy available for release in a chemical reaction

Free energy

Energy that is available to do work

Enzymes

-ase. Each is made for a specific action/purpose.

Catabolic

Breaking down

Anabolic

Building up

Proteins

Nutrients the body uses to build and maintain its cells and tissues (chains of amino acids)

Steroids

A type of lipid characterized by a carbon skeleton consisting of four rings with various functional groups attached

Phospholipids

A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail

Triglycerides

An energy-rich compound made up of a single molecule of glycerol and three molecules of fatty acid

Primary protein structure

Sequence of amino acids (held together through peptide bonds)

Secondary protein structure

Coiling or folding of a polypeptide due to hydrogen bonding between amino acids

Tertiary protein structure

3D folding pattern of a protein due to side chain interactions of amino acids (hydrogen bonds between polar side chains and ionic bonds between negatively and positively charged side chains)

Quaternary protein structure

2+ protein chains forming functional protein. A 'braided' chain of two or more entirely identical or entirely different polypeptide chains.

Protein denaturation

When proteins are subject to heat, acid or other conditions that disturb their stability; protein uncoils, loses its shape, and loses its function