2.3: Macromolecules

Macromolecules large organic molecules called polymers made up of smaller “building blocks” called monomers the four to remember: carbohydrates lipids nucleic acids proteins

Organic Compounds compounds that contain CARBON are called organic other than water, most compounds in your body are organic

Carbon (C) carbon has 4 electrons in outer shell –needs 8 carbon can form covalent bonds (share electrons) with as many as 4 other atoms usually bonds with: carbon (C) hydrogen (H) oxygen (O) nitrogen (N)

Carbohydrates

carbohydrate: carbon, hydrogen, & oxygen in a 1:2:1 ratio [ chemical formula: C6H12O6 ] key source of energy basic building block (monomer) is a “simple sugar” – monosaccharide - like glucose (also fructose & galactose) -OSE ending means SUGAR

disaccharide: “double sugar” unit like sucrose, lactose, & maltose glucose polysaccharide: “many sugar” units like starch, glycogen, & cellulose glucose cellulose

Lipids

has no true monomer but are formed from combinations of glycerol and fatty acids general term for compounds which are not soluble in water examples: fats oils waxes steroid hormones phospholipids

functions of lipids: long term energy storage (fats, oils) protection against heat loss, water loss, & physical shock (waxes) chemical messengers (hormones) major component of membranes (phospholipids)

Nucleic Acids

nucleic acid: long chains of smaller building blocks (monomers) called nucleotides two types of nucleic acids: DNA & RNA

Nucleotide O O=P-O N CH2 O C1 C4 C3 C2 Phosphate Nitrogen base Group 5 Sugar

DNA: deoxyribonucleic acid stores heredity information (instructions!) RNA: ribonucleic acid helps in making of proteins & can act as an enzyme

Proteins

are 20 amino acids in nature protein: large molecule formed by linking smaller building blocks (monomers) called amino acids are 20 amino acids in nature amino acids are different based on their “R” group

functions of proteins: transport: carry oxygen from lungs to other parts of body (hemoglobin) regulatory: hormones, antibodies movement: muscles structural: skin, hair & nails (collagen), fibers in blood clots enzymes: promote cellular reactions