Unit 1 Notes: Biological Elements & Biomolecules

(1) Atoms, Energy & Living Things All living things are made of atoms: Missing valence electrons drive all chemical reactions inside living things. Atoms bond together to gain full valence shells and become stable. All living things require energy in order to complete life processes.

(2) Biological Elements CHONPS (Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur) These 6 elements are found in all living things. Carbon bonds form the framework for all major molecules found in living systems.

(3) Why is Carbon So Special? Carbon has 4 valence electrons. Carbon can form up to four bonds with other atoms. This allows Carbon to form lots of different types of structures and molecules, all with different functions.

(4) The Biomolecules Carbohydrates (Carbs) Lipids (Fats) Protein Nucleic Acids These are the 4 molecules that make up all living things, each composed of CHONPS.

(5) Carbohydrates Structure: Functions: Monomer: Monosaccharides (Single Sugars) Examples  Glucose, Fructose Polymer: Polysaccharides (Many Sugars) Examples  Starch, Cellulose, Glycogen Functions: Provide immediate and intermediate energy to cells. Shorter Chains = Faster, Shorter Lasting Energy Longer Chains= Slower, Longer Lasting Energy

(6) Lipids Structure: Functions: Monomer: Fatty Acids and Glycerols Polymer: Lipid Examples  Phospholipids, Oils, Cholesterol, Triglycerides Functions: Provide long term energy storage to cells. Phospholipids form protective cell membranes.

(7) Proteins Structure: Functions: Monomer: Amino Acids Polymer: Polypeptide (Many Peptide Bonds) Examples  Hemoglobin, Protein Channels, Antibodies, Enzymes Functions: Proteins are the expression of DNA. Hemoglobin allows red blood cells to bind with gas. Protein Channels allow specific molecules to travel in and out of cells. Antibodies help identify infectious agents. Enzymes catalyze (speed up) chemical reactions by lowering the energy of activation required.

(8) Nucleic Acids Structure: Functions: Monomer: Nucleotides Made of  Pentose Sugar, Phosphate, Nitrogenous Base Polymers: DNA and RNA Functions: Store genetic information. Allow for the production of proteins.