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:– Monomer: Monosachcarides (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:– 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:– 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:– Monomer: Nucleotides• Made of Ribose Sugar, Phosphate, Nitrogenous Base

– Polymers: DNA and RNA

• Functions:– Store genetic information.– Allow for the production of proteins.