The Size of Cells and Their Components

Organic Compounds- Living organisms are made

up of organic compounds - CHNOPS - main elements found in

living organisms

- All organic compounds contain carbon(exceptions: CO2, CO, CaCO3)

- Carbon can form 4 covalent bonds

- Carbon based molecules form chains, branched chains, rings, etc.

4 Classes of Organic Compounds:1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic Acids

Carbohydrates- contain C, H, O (1:2:1) - include sugars, starches,

cellulose - used for energy storage and

to build cell walls - names usually end in "-ose"

Lipids- fats, oils, waxes, steroids - not soluble in water - more energy (calories) in

lipids than in carbohydrates- energy storage, insulation,

cell membrane, coatings

Cell Membrane

Phospholipid bilayer

Proteins:- the most abundant and

varied of organic compounds

- contain C, H, N, O (S)

A. Types of protein1.Structural: - keratin (hair,

fingernails), collagen2.Contractile: - actin and

myosin (muscle) 3.Pigments: - melanin (in

skin, hair, iris)

4.Hormones: - regulate body functions (insulin)

5.Antibodies: - fight disease6.Enzymes: - amylase (in

saliva), lactase

Amino Acids- building blocks of proteins- 20 different amino acids- proteins contain between 50

- 2000 amino acids

Nucleic Acids- 2 major types:A.DNA

- contains hereditary information (genes) - double helix

B. RNA- controls protein synthesis - single helix