organic molecules

Carbohydrates

carbon, hydrogen, and oxygen (CH20)

sugars and starches

Short-term energy (glycogen for animals and starch for plants)

some are used for structure (cellulose plant cells and chitin fungi cell walls)

monosaccharides are monomers of carbohydrates they include simple sugars like glucose, fructose, and galactose

Disaccharides are 2 monosaccharides bonded together (sucrose = glucose + fructose)

Polysaccharides are 3 or more monosaccharides bonded together (starches, cellulose, chitin, and glycogen)

Lipids

Carbon, hydrogen, and oxygen (C-H-O) 1:2: very few

made of long hydrocarbon chains

primarily fats, oils & waxes

nonpolar molecules used for long-term energy

essential components of cell membranes

Fatty Acids are the monomers of lipids that have a hydrophilic end and a hydrophobic end

no true polymer

triglycerides are large lipids composed of three fatty acids and one molecule of glycerol

Saturated vs. Unsaturated fats

Saturated fats are hydrocarbon chains with only single bonds that are mainly from animals and solid at room temp

Unsaturated fats have hydrocarbon chains with both double and single bonds which are mainly from plants and are liquid at room temperature

Other examples of lipids

phospholipids

• make up cell membranes

• have a polar head and nonpolar tail

waxes are one long fatty acid chain joined to an alcohol

• protect animal ears and plant leaves

Steroids are composed of four fused carbon rings that help to regulate body functions

• testosterone and estrogen

• cholesterol is found in cell membranes contributing to permeability (letting things in and out)

Proteins

Carbon, hydrogen, oxygen, and nitrogen

proteins have many functions

• structural as muscle fiber collagen & keratin

• defensive as antibodies in immune system

• enzymes are catalyzing (speed up) chemical reactions

Amino acid

• monomer of proteins

• 20 different types identified by their R group

• 2 amino acids joined by a peptide bond

Polypeptides

• 3 or more amino acids bonded together by peptide bonds

• usually 1000’s of amino acids

Protein structure

• chains of amino acids that are folded into complex shapes to fit their jobs

• structure → function

Nucleic acids

nucleic acid is composed of carbon, hydrogen, nitrogen, oxygen & phosphorus

they are used to store and transmit genetic information

• DNA stores information

• RNA transmits information

The monomers of nucleic acids are called nucleotides

• they contain 5- 5-carbon sugar, nitrogenous base & phosphate group

A polymer of nucleic acids is called a polynucleotide

DNA contains genetic information for cell activities

• double stranded