BiochemistryChapter 6

The element carbon is a component of almost all biological (organic) molecules.

Carbon has 4 electrons in its outermost energy level.

Carbon compounds can be straight chains, branched chains, and rings.

Carbon can share 1, 2, or 3 pairs of electrons with another atom

Functional groups influence molecule characteristics

Hydroxyl –OH OCarboxyl –C-OH

HAmino N-H

OPhosphate -O-P-OH OH

Macromolecules large molecules formed by joining smaller organic molecules

Polymers molecules made from repeating units of identical or nearly identical compounds linked together by covalent bonds

Condensation Reaction-water is released each time a monomer is added to a polymer

Hydrolysis-water breaks down a polymer

Reverse of each other

Energy Currency adenosine triphosphate-ATP

Bonds between the phosphate groups are less stable

When bond is broken, (hydrolysis) energy is released

Carbohydrates

Compounds composed of carbon, hydrogen, and oxygen in a ratio of one oxygen and two hydrogen atoms for each carbon atom—(CH2O)n

Values of n ranging from three to seven are called simple sugars, or monosaccharides.

Two monosaccharides joined together form a disaccharide.

Longer carbohydrate molecules are called polysaccharides.

Proteins

A compound made of small carbon compounds called amino acids

Amino acids have a central carbon atom.

One of the four carbon bonds is with hydrogen.

The other three bonds are with an amino group (–NH2), a carboxyl group (–COOH), and a variable group (–R).

The number and the order in which the amino acids are joined define the protein’s primary structure.

After an amino acid chain is formed, it folds into a unique three-dimensional shape, which is the protein’s secondary structure, such as a helix or a pleat.

LipidsMolecules made mostly of carbon and hydrogen

A triglyceride is a fat if it is solid at room temperature and an oil if it is liquid at room temperature.

Lipids only single bonds - saturated fats.

Lipids at least one double bond - unsaturated fats.

Fats more than one double bond - polyunsaturated fats.

Phospholipids Made of a glycerol,

phosphate group and 2 fatty acid chains

2 layers of these-bilayer-makes up cell membranes

Nucleic acids - complex macromolecules that store and transmit genetic information-DNA, RNA

Nucleic acids are made of smaller repeating subunits called nucleotides, made of carbon, nitrogen, oxygen, phosphorus, and hydrogen