Ch 2.3 Outline
III. Carbon Compounds
- The Chemistry of Carbon
- Why is carbon so interesting for scientists?
- Carbon atoms have 4 electrons available for bonding which can form strong covalent bonds with other molecules and compounds.
- Carbon can bond with hydrogen, oxygen, phosphorous, sulfur and nitrogen. These are the elements of Organisms.
- Carbon atoms can bond with each other. Bonding between carbon atoms gives carbon the ability to form chains that can be unlimited in length
- These carbon bonds can be single, double and triple covalent bonds
- They can also form a carbon ring
- No other element comes close to matching carbons ability to make so many different compounds.
- Macromolecules
- Many of the carbon compounds are so large that they are known as Macromolecules or “giant molecules”.
- Macromolecules are made from thousands or even hundreds of thousands of smaller molecules (monomers) linked together.
- Monomers link together to form polymers, polymers link together to form macromolecules.
- 4 major groups of macromolecules in living things: carbohydrates, lipids, nucleic acids and proteins.
- Carbohydrates – compounds made up of carbon, hydrogen and oxygen atoms
- There are usually twice as many hydrogen atoms as carbon or oxygen atoms in carbs
- Living things use carbohydrates as their main source for energy
- Sugars are carbs
- Sugars are any words that end in “ose” (ex: glucose, sucrose, fructose)
- Simple sugars
- Monosaccharides = simple sugar molecules (ex: Galatose and Fructose)
- Disaccharides = made of 2 sugar molecules (ex: Sucrose which is made of glucose and fructose)
- Polysaccharides = made of 3 or more sugar molecules
- Complex carbohydrates– the large macromolecules formed when simple sugars join together.
- Many animals store extra sugar in the form of complex carbohydrates called glycogen. When your blood sugar levels are low, glycogen is broken down into glucose which goes into the blood stream and returns blood sugar levels to normal.
- The glycogen stored in your muscles gives energy to muscles so that you can move.
- Plants store complex carbohydrates in the form of starch. They also store it as Cellulose which gives plants their rigidity and strength.
- Lipids– macromolecules that generally do not dissolve in water and are mostly made up of carbon and hydrogen atoms.
- Most common lipids are waxes, fats and oils
- Produce waterproof coverings on cells and tissues
- Some store energy
- Saturated fats – carbon atoms held together with a single bond; are solids at room temp.
- Unsaturated fats – at least 1 carbon – carbon atom is held together with a double bond; liquid at room temp.
- Nucleic Acids – macromolecules containing hydrogen, oxygen, nitrogen, carbon and phosphorus.
- Nucleic acids are polymers
- Made up of monomers called nucleotides
- Have 3 parts:
- 5-carbon ringed sugar
- A phosphate group
- A nitrogenous base
- Nucleotides Includes ATP – primary nucleotide for the bodies energy storage
- 2 kinds of nucleic acids
- Ribonucleic acid (RNA) – contains the sugar Ribose
- Deoxyribonucleic acid (DNA) – contains the sugar deoxyribose
- The key function is to store and transmit genetic information
- Proteins– macromolecules that contain a nitrogenous base as well as carbon, hydrogen, and oxygen.
- Proteins are polymers of amino acids
- Covalent bonds called peptide bonds link amino acids together to form polypeptides
- Functions- Some proteins control cell processesand the rate of reactions. Others form important parts in cells, which still others move substances into or out of cells or help fight disease.
- Structure and function
- More than 20 amino acids are found in nature
- All amino acids are the same in the regions where they may be joined together by covalent bonds which allows them to join together with many amino acids
- Levels of structure
- Amino acids are joined in long chains according to instructions coded in DNA.
- There are 4 levels of structure = the amino acid order, the folding of the polypeptide chain, 3D arrangement of a chain, and describes how different chains are placed together.