Chapter 2

Basic Biochemistry

Biochemistry: Essentials for LifeBiochemistry: Essentials for Life

• Organic compounds

• Contain carbon

• Most are covalently bonded

• Example: C6H12O6 (glucose)

• Inorganic compounds

• Lack carbon

• Tend to be simpler compounds

• Example: H2O (water)

Important Inorganic CompoundsImportant Inorganic Compounds

Water

1. Most abundant inorganic compounds

2. Vital properties

a) High heat capacity

b) Polarity/solvent properties

c) Chemical reactivity

d) Cushioning

Salts

1. Easily dissociate into ions in the presence of water

2. Vital to many body functions

3. Include electrolytes which conduct electrical currents

Important Inorganic CompoundsImportant Inorganic Compounds

Cube of NaCl

Acids

• Can release detectable hydrogen ions (protons)

• Your stomach produces a strong acid to kill pathogens and begin digestion (HCl)

Bases

• Proton acceptors

• Antacid medications like Tums and Peptobismol contain bases.

Neutralization reaction

• Acids and bases react to form water and a salt

AcidsAcids && BasesBases

HCl + NaHCO3 H2O + NaCl + CO2

pHpH• Measures relative

concentration of hydrogen ions

• pH 7 = neutral

• pH below 7 = acidic

• pH above 7 = basic

• Buffers are chemicals that can regulate pH change

AcidsAcids && BasesBases

Important Organic CompoundsImportant Organic Compounds

Carbohydrates

• Contain carbon, hydrogen, and oxygen

• Include sugars and starches

• Used by the body for energy

• Classified according to size

• Monosaccharides – simple sugars

• Disaccharides – two simple sugars joined by dehydration synthesis

• Polysaccharides – long branching chains of linked simple sugars

CarbohydratesCarbohydrates

Important Organic CompoundsImportant Organic Compounds

Polysaccharide

CarbohydratesCarbohydrates

Important Organic CompoundsImportant Organic Compounds

AKA Complex Carbohydrates

Lipids

1. Contain carbon, hydrogen, and oxygen; carbon and hydrogen outnumber oxygen

2. Insoluble in water

3. Used in the body for forming the cell membrane, hormone and vitamin production,

energy storage, cushioning and

insulation

Important Organic CompoundsImportant Organic Compounds

Common lipids in the human body:

1. Neutral fats (triglycerides)

a) Found in fat deposits

b) Composed of fatty acids and glycerol

c) Source of stored energy

2. Phospholipids - form cell membranes

3. Steroids - Include cholesterol, bile salts, vitamin D, and some hormones

Important Organic CompoundsImportant Organic Compounds

Lipids: Trigylcerides & PhospholipidsLipids: Trigylcerides & PhospholipidsImportant Organic CompoundsImportant Organic Compounds

Saturated vs. Unsaturated Fats1.Saturated fats have all single bonds. They are saturated with hydrogen atoms. (tend to be solid at room temperature.)2.Unsaturated fats have one or more (polyunsaturated) double bonds between carbon atoms. (tend to be liquid at room temperature.)

Important Organic CompoundsImportant Organic Compounds

Lipids: CholesterolLipids: Cholesterol

Important Organic CompoundsImportant Organic Compounds

Proteins…They do everything!!

1. Made of amino acids

2. Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur

3. Plays a vital role in cell function

a) Provides for construction materials for body tissues

b) Act as enzymes, hormones, and antibodies

4. Account for over half of the body’s organic matter

Important Organic CompoundsImportant Organic Compounds

Important Organic CompoundsImportant Organic Compounds

Proteins – Structure determines function

Proteins: EnzymesProteins: Enzymes1. Act as biological catalysts

2. Increase the rate of chemical reactions

Important Organic CompoundsImportant Organic Compounds

Nucleic AcidsNucleic Acids

1. Encode protein recipes

2. Nucleotide bases

a) A = Adenine

b) G = Guanine

c) C = Cytosine

d) T = Thymine

e) U = Uracil

3. Make DNA and RNA

Important Organic CompoundsImportant Organic Compounds

Deoxyribonucleic acid (DNA)

1. Provides instruction for every protein in the body

2. Organized by complimentary bases to form double helix

3. Replicates before cell division

Important Organic CompoundsImportant Organic Compounds

Nucleic AcidsNucleic Acids

Important Organic CompoundsImportant Organic Compounds

Important Organic CompoundsImportant Organic Compounds