The Chemistry of Life

Bonds

• Bond is a force that holds atoms together

O H H

Covalent bonds

• Force that holds 2 atoms together when they share electrons

Ionic bonds

• Atoms bond with each other by gaining or losing electrons in outer shells, opposite forces attract– Example: sodium loses an electron to become

stable

chlorine gains an electron and becomes stable

Compound

• Substance composed of atoms that are bonded together

• Examples:

• 2 types– Organic compounds: contain carbon rings or

chains– Inorganic: don’t have carbon rings or chains

Look at p. 51 fig. 3-1 organic or inorganic

PP: What is a monomer, polymer, and macromolecule?

Read 1st paragraph on p. 53 and define those words.

Carbohydrates“Carbon Water”

• C, H, O• Always Ratio of 2

Hydrogens to 1 Oxygen CH2O

• Main Role in Body:– Simple Carbs (Sugars)

• Immediate Energy but doesn’t last long

– Complex Carbs (Starches)

• Longer lasting energy but not immediate

Monosaccharide“One Sugar”

• Monomer unit of carb• C6H12O6

• Types:– Glucose- made by plants– Fructose-Fruits

• OSE-ending= Oh So SwEEEt

• Simple Sugar• Isomer- different

structures but same chemical formula

Disaccharide“Two Sugars”

• Two monosaccharides linked together

• Types:– Sucrose- Table Sugar– Lactose- Milk Sugar

• C12H22O11

• Simple Sugar

Polysaccharide“Many Sugars”

• 1000s of monosaccharides linked

• Complex carb: provides long sustaining energy but must be broken down first

Types of Polysaccharides

• Starch– Made by plants for energy storage– We can get energy by eating these– Potatoes, Pastas, Breads etc

• Glycogen– Made by animals for limited energy storage– Stored in liver and muscle

• Cellulose– Made by plants for structure– We cannot digest this for energy: It is fiber– Leafy veggies, CELLERY, grass

Lipids

• Elements: C, H, O (much less O)

• Will NOT dissolve in water

• Main Functions:– Fats: store energy,

padding, and insulation– Wax: waterproof, forms

protective layers– Oil: protects skin, hair,

feathers

Fatty Acid

• Monomer of Lipid• Saturated Fatty Acid:

Full amount of Hydrogens

• Unsaturated Fatty Acid: Missing hydrogens due to double bond Carbons

• Head end: hydrophilic• Tail end : hydrophobic

Common Fats

• Saturated– Made by animals (lard)– Solid at room temp– Made with saturated

Fatty Acids

• Unsaturated– Made plants- OILS– Liquid at room temp– Made with unsat FAs

Other Types of Lipids

• Wax– Waterproofing agent– Earwax, candle wax

• Steriods– Make up hormones like

testosterone

Proteins

• C, H, O, N • Nitrogen is not in

carbs or lipids• Types:

– Structural:• Muscle, hair, enzymes

– Enzymes: • speed up chemical

reactions

Amino Acids

• Monomer of Proteins• 20 Different Kinds• R group is the group

that makes each amino acid different

Peptide Means protein

• Peptide bond- bond between two amino acids

• Dipeptide- two amino acids linked

• Polypeptide- many amino acids linked

Nucleic Acids

• 2 types– DNA (deoxyribonucleic

acid) in nucleus, in chromosomes, molecule of heredity

– RNA (ribonucleic acid) makes proteins, ribosomes

htt/www.ericharhbarger.org/lego/images/dna/trans_0.jpg

Organic or Inorganic?

• N3H4

• C6H12O6

• C12H22O11

• C18H42O3