Life substances

1. Life substances The Role of Carbon in Organisms

2. ??? • How many different words can you make from the letters: R T A E ?

3. ??? • Think about the amount of words you could make from only 4 letters. Now explain how only 90 natural elements could form all of the different substances on Earth.

4. Structure of carbon • 4 electrons in its outer shell = 4 covalent bonds • Allows for different shapes of structures • Allows for diversity in carbon compounds

5. Structure of carbon • Isomers – compounds that have the same chemical formula, but differ in three dimensional shape. • Polymers of carbon are large molecules made from many smaller carbon molecule units (sugars  starches)

6. Carbohydrates • Provide energy (esp. for nervous system) • C, H, O - 1:2:1 • Simple sugars = monosaccharides • Monosaccharides can link together to form a polysaccharide – starch

7. Lipids • Mostly carbon and hydrogen w/ very little oxygen • Fats, oils, steroids • Glycerol “backbone” w/ fatty acids attached = glyceride • Functions: energy storage, insulation, protective coverings; major component in membranes

9. Proteins • Made of C, H, O, N, and sometime S • Monomer = amino acid (20 common ones) • Combinations of amino acids can make thousands of different 3-D proteins

10. Proteins • Amino acids are linked together through dehydration synthesis creating a peptide bond • Enzyme is a protein catalyst; it is used to speed up a reaction, usually by lowering its activation energy, but is not used up in the reaction

12. Nucleic Acids • Complex molecule used to store hereditary info • Monomers = nucleotide = sugar, nitrogenous base, phosphate group • Made up of C, H, N, P, and O

13. Nucleic Acids • Found in DNA and RNA – named for the sugar found on the nucleotides • DNA is the gene sequence found in all organisms • RNA is used in protein synthesis in various ways