Molecules of Life
	Molecules of Life
		“Organic Molecules”
			Carbon based
			Found in living systems
			Made from very few elements
			Composed of “building blocks” joined together
			Include 4 different classes of molecules
	Molecules of Life
 		Very few elements needed
			95% living matter composed of just 4 elements
				Carbon
				Hydrogen
				Nitrogen
				Oxygen
			98% living matter 2 elements added
				Phosphorus
				Sulfur
			Vertebrate organisms also contain 2% calcium
	Molecules of Life
 		4 Different Classes of Organic Molecules
			Proteins
			Carbohydrates
			Lipids
			Nucleic Acids (see ch. 23)
	Molecules of Life
 		“Building” Organic Molecules
			Single building blocks = monomer
			Join 2 monomers = dimer
			Join 3 monomers = trimer
			Join many monomers = polymer
	Molecules of Life
 		How do “amino acids” join to form protein?
			Amino acids have 2 ends
				amino group (NH2)
				carboxylic acid group (COOH)
			H atom from the amino end joins with an OH group from the carboxylic acid end to form “H20”
			The H20 molecule moves away & the 2 amino acids are joined by a “peptide” bond
			More amino acids join in the same way and a long chain is formed
	Molecules of Life
		Proteins include:
			Physical structures such as hair & muscle
			Enzymes which speed up chemical reactions
			Complex molecules such as hemoglobin
	Molecules of Life
		Proteins have 3 or 4 levels of structure
			Primary – sequence of amino acids in chain
			Secondary – way sequence kinks or bends
			Tertiary – shape of the folded protein
			Quaternary – 2 or more chains joined together (only some proteins have this level of structure)
	Molecules of Life
		Carbohydrates
			include simple sugars like glucose
			include polysaccharides such as starch and cellulose (plants)
			include polysaccharides such as glycogen (animals)
			are molecules which provide energy and/or support
	Molecules of Life
		Lipids
			Made from units containing fatty acids + glycerol
			Saturated (no double bonds) or unsaturated (at least one double bond)
			Include fats, waxes, oils, phospholipids
			Provide energy, insulation, weather-proofing, cell membranes
	Molecules of Life
		Also necessary for life in small quantities
			Minerals
				Calcium, potassium, sodium, magnesium, chlorine, iodine
				Not organic
			Vitamins
				Complex organic molecules
				Water-soluble, renew daily
					B family + C
				Fat-soluble, can be stored
					A, D, E, K
				All but D must be supplied by our food