molecules of life chapter 22 great idea: a cell’s major parts are constructed from a few simple...
TRANSCRIPT
Molecules of Life
Chapter 22
Great Idea:A cell’s major parts are constructed from a few
simple molecular building blocks
Chapter Outline
• Organic Molecules
• Proteins: The Workhorses of Life
• Carbohydrates
• Lipids
• Minerals and Vitamins
Four Basic Characteristics• Most molecules based on chemistry of carbon
– Organic molecules
• Life’s molecules form from few elements– H, O, C, N97.5% of body weight
• Molecules composed of simple building blocks– Arranged differently
• Shape determines behavior– Determines ability for bonding
Amino Acids: The Building Blocks of Proteins
• Amino Acid– Carboxyl group– Amino group– Carbon atom– Side group
Amino Acids cont.
• Bonding– Two amino acids
• H bonds with OH • Forms H2O • Forms peptide bond
– Polypeptide• chain
• Protein– Large molecule– Chain of amino acids
• Only 20 amino acids in living organisms
How Drugs Work
• Blocking enzymes– Block active site– Molecules cannot bond– Reaction does not take place
• Shape of molecules– Block membrane transport– Block neurotransmitters
Carbohydrates
• Structure– C, H, O
• Simplest– Sugars
– CnH2nOn
• Monosaccharides
• Polysaccharide
• Starches
• Cellulose
Lipids
• Lipids– Insoluble in water
• Role of lipids– Cell membranes
– Store energy
• Phospholipids– Make up cell
membrane
Saturated and Unsaturated Fats
• Saturated– C is fully bonded– Basis of cholesterol
• Unsaturated– Monounsaturated– Polyunsaturated
• hydrogenation
Lipids - molecules with large nonpolar areas soluble in nonpolar solvents:
A triglyceride is a fat or an oil. If the chain contains double bonds the fat is unsaturated.