Chapter 8, Sections 1 & 4 Carbon Chemistry

Carbon Has the ability to combine in many ways with itself and other elements Has a central role in the chemistry of living organisms

Carbon Atoms & Bonding Atomic # of Carbon = 6 – 6 protons – 6 electrons – 4 valence electrons (can form 4 bonds) Carbon is capable of forming long chains or molecules of thousands of carbon atoms Carbon atoms can form straight chains, branched chains, and rings

Table Talk: What happens to carbon’s valence electrons when it bonds with other elements? What type of bonds do they form?

4 classes of organic compounds required by living things Carbohydrates Proteins Lipids Nucleic acids These are all nutrients!

Carbohydrates Energy-rich Compound made of carbon, hydrogen, & oxygen carbo means “carbon” and hydrate means “combined with water” Simplest carbs are sugars – Sucrose = white sugar in cookies, candy, etc. – Important body sugar is glucose C 6 H 12 O 6 – “blood sugar”

Complex Carbohydrates Plants or food products made from plants Energy-rich – Starch (bread, cereals, pasta, rice, potatoes) – Cellulose (fiber) is undigestible

Table Talk: What do all carbohydrates have in common, and why is it important to include them in your diet?

Proteins Muscle, hair, skin and fingernails are made of protein The body uses proteins from food to build and repair body parts and to regulate cell activities Different proteins are made when different sequences of amino acids are linked in chains Meat, eggs, fish, nuts, soy, and milk or milk products

Table Talk: Why do body builders take protein supplements?

Lipids Energy rich Made of carbon, oxygen and hydrogen Fats, oils, waxes, and cholesterol Each fat is made from 3 fatty acids and one alcohol named glycerol At room temperature, fats are solid; oils are liquid

(Lipids, contd.) Cholesterol – Found in animal cells only – Used to build cell structures and form compounds that serve as chemical messengers – Unlike other lipids, is NOT a source of energy – The body produces the cholesterol it needs, but it is also ingested through foods that come from animals

Nucleic Acids Very large, organic molecules made of carbon, oxygen, hydrogen, nitrogen, and phosphorus Two types: – DNA – RNA When living things reproduce, they pass DNA and the genetic information it carries to the next generation

Other Nutrients Living organisms are made mostly of: – Carbon – Hydrogen – Nitrogen – Oxygen – Phosphorus – Sulfur To support the functioning of large molecules, organisms require: – Water – vitamins – Minerals – salts See BrainPop “Body Chemistry” end