Carbon Compounds Section 2.3

Bellwork What are the functions of the four groups of macro molecules? Carbohydrates – source of energy Lipids – store energy Nucleic acids – store hereditary and genetic information Proteins – Control reaction rates and regulate cell processes or form cell structures Or transport things in and out of cells Or help fight disease

Carbon properties Due to carbon’s 4 valence electrons, carbon can bond with MANY other elements Most common are Hydrogen Oxygen Phosphorous Sulphur Nitrogen This is the basis for the molecules of life, the basis of all living organisms

What compounds contain carbon? Carbon dioxide Carbon monoxide Chalk Carbon Sugar Protein Crude oil Alcohol Fats Nucleic acids

Chains of carbon Acetylene Methane Carbon can also bond with itself Can give rise to chains of nearly unlimited length Single, double, or triple covalent bonds Can also form rings Millions of possibilities for large and complex structures Carbon is the most versatile element on earth Acetylene Methane

Macromolecules Giant molecules 4 major groups of macro molecules Made of thousands, or hundreds of thousands of giant molecules Most formed via polymerization Large compound built by joining smaller ones together Smaller unit – monomer Can be identical or different Larger unit – polymer 4 major groups of macro molecules Carbohydrates Lipids Nucleic acids Proteins

Polymerization = + Two types of polymerization Addition Condensation Monomers join together with no change in their molecule Condensation A small molecule is released when two monomers are joined together Often water = +

Hydrolysis = + H2O Both condensation reactions and hydrolysis are extremely common biochemical processes

Carbohydrates Carbon, hydrogen and Oxygen Ratio – 1:2:1 Main source of energy in all living things Also sometimes used for structural purposes Breakdown of sugars provides energy Excess sugars stored in complex carbohydrates – starches In starch glucose is the monomer

Simple sugars (monosaccharides) Glucose most common Other examples galactose (in milk), fructose (in fruit), Basic building block of carbohydrates Sucrose (ordinary sugar) is a disaccharide Made from combining glucose and fructose – two simple sugars

Complex Carbohydrates – polysaccharides Formed from many monosaccharides Plants store sugar in a polysaccharide called starch Stores excess sugar Cellulose – another examples of a polysaccharide Also provides strength and rigidity to a plant Glycogen – example of polysaccharide in humans How animals store excess sugar - “animal starch” When we have low blood sugar levels, the body breaks down glycogen to glucose Glycogen in muscles supplies energy for muscle contraction and movement

Lipids Mostly made of carbon and hydrogen Not soluble in water A large and varied group Common categories are fats, oils and waxes Formed from glycerol combing with a fatty acid Two types of fatty acids Saturated Unsaturated

Fatty acids Saturation is related to the number of hydrogen atoms If it contains the maximum possible number it is saturated Otherwise it is unsaturated If the fatty acid contains one C to C double bond it is unsaturated If it contains more than one C to C double bond it is polyunsaturated Unsaturated fatty acids tend to be liquid at room temperature E.g. Olive oil Can also help to lower blood cholesterol levels Data exercise Page 48

Nucleic acids Hydrogen, oxygen, nitrogen, carbon and phosphorous Made from nucleotides Nucleic acids store and transmit hereditary or genetic information Ribonucleic acid (RNA) Deoxyribonucleic acid (DNA)

Protein Contain nitrogen alongside carbon, hydrogen and oxygen Polymers of molecules called amino acids Amino acids have Amino group – NH2 Carboxyl group – COOH Covalent bonds called peptide bonds link amino acids together via a condensation reaction

Peptide bond formation

Protein Functional molecule built from one or more polypeptides Proteins can: control the rate of a reaction regulate cell processes form important structures transport substances in or out of cells help fight disease

Structure and Function More than 20 amino acids are found in nature All have carboxyl and amino groups Any amino acid can be joined to another through covalent bonds Side chain group (R group) provides differences Gives rise to a large number of different properties and functions Acidic, basic, polar, non polar…. Information on how amino acids should be assembled is stored In DNA

Levels of organization The shape of a protein is determined by a number of forces Ionic bonds Covalent bonds Hydrogen bonds Van der waals forces Shape can be very important for a proteins function enzyme