BiochemistryBiochemistry

Exploring MacromoleculesExploring Macromolecules

Organic ChemistryOrganic Chemistry

- study of chemistry of carbon- study of chemistry of carbon

- molecules of life made of elements carbon, - molecules of life made of elements carbon,

oxygen, nitrogen, and hydrogenoxygen, nitrogen, and hydrogen

- - functional groupsfunctional groups – determines the – determines the

characteristics of that compoundcharacteristics of that compound

Hydroxyl goup: -OH Hydroxyl goup: -OH (see fig. 2)(see fig. 2)

Carboxylic acid group: -COOH Carboxylic acid group: -COOH (see fig. 3)(see fig. 3)

Amine group: -NHAmine group: -NH22 (see fig. 4)(see fig. 4)

Large carbon molecules = Large carbon molecules = macromoleculesmacromolecules

- large polymers – composed of repeating units - large polymers – composed of repeating units

called monomerscalled monomers

- monomers are joined in condensation or - monomers are joined in condensation or dehydration synthesis reactions to form dehydration synthesis reactions to form polymers polymers (fig. 5)(fig. 5)

- breaking polymers down into monomers occurs - breaking polymers down into monomers occurs by hydrolysis reactionsby hydrolysis reactions

- four main classes of macromolecules:- four main classes of macromolecules:

*Proteins * Carbohydrates * Lipids * Nucleic Acids *Proteins * Carbohydrates * Lipids * Nucleic Acids

ProteinsProteins- composed of amino acids = monomers- composed of amino acids = monomers

- all amino acids have a:- all amino acids have a:

a. carboxyl group –COOHa. carboxyl group –COOH

b. amine group –NHb. amine group –NH22

- 20 common amino acids in living organisms- 20 common amino acids in living organisms

- joined by peptide bonds- joined by peptide bonds

= = polypeptidepolypeptide

- sequence of amino acids- sequence of amino acids

determines protein’sdetermines protein’s

structure and functionstructure and function

- [examples]- [examples]

- primary structure = sequence of amino acids- primary structure = sequence of amino acids

- R groups often form attractions that cause the - R groups often form attractions that cause the protein to fold protein to fold (add the following to handout)(add the following to handout)

- - secondary structure = regular foldingsecondary structure = regular folding

- tertiary structure = irregular folding- tertiary structure = irregular folding

- quaternary structure = more than one - quaternary structure = more than one polypeptide joined to make a functional polypeptide joined to make a functional proteinprotein

- - DenaturingDenaturing a protein changes its shape a protein changes its shape

- change in temperature or pH - change in temperature or pH

HemoglobinHemoglobin

(fig. 6 and 7)(fig. 6 and 7)

Primary structure

Secondary

Tertiary

Quaternary

CarbohydrateCarbohydrate- general formula C- general formula Cnn(H(H22O) O)

- provide energy- provide energy

- exist as monosaccharides, disaccharide, - exist as monosaccharides, disaccharide, polysaccharidespolysaccharides

- monomers = monosaccharides - monomers = monosaccharides (glucose/fructose)(glucose/fructose)

- monosaccharides are linked by condensation - monosaccharides are linked by condensation reactionsreactions

- sucrose is a disaccharide - sucrose is a disaccharide (fig. 8)(fig. 8)

- three important polysaccharides- three important polysaccharides

a. glycogen – animal energy a. glycogen – animal energy

storagestorage

b. starch – plant storageb. starch – plant storage

c. cellulose – in plant cell wallsc. cellulose – in plant cell walls

LipidsLipids- large nonpolar molecules that are not very - large nonpolar molecules that are not very soluble in watersoluble in water

- very efficient energy storage molecules – store - very efficient energy storage molecules – store twice as much energy as carbohydratestwice as much energy as carbohydrates

- simplest are fatty acids with long, straight carbon - simplest are fatty acids with long, straight carbon chain with a –COOH, carboxyl group, at one chain with a –COOH, carboxyl group, at one endend

- carbon chain is hydrophobic (water fearing)- carbon chain is hydrophobic (water fearing)

- carboxyl group end is hydrophilic (water loving)- carboxyl group end is hydrophilic (water loving)

- form membranes of cells (- form membranes of cells (phospholipidsphospholipids) ) (fig. 10)(fig. 10)

- saturated fats have all single bonds- saturated fats have all single bonds

- unsaturated fats have some multiple bonds- unsaturated fats have some multiple bonds

- Four basic categories:- Four basic categories:

a. Triglyceridesa. Triglycerides

b. Phospholipids b. Phospholipids

c. Waxesc. Waxes

d. Steroids – d. Steroids – ex. Cholesterol andex. Cholesterol and

hormoneshormones

Nucleic AcidsNucleic Acids- transmit genetic information- transmit genetic information

- DNA and RNA- DNA and RNA

- DNA carries genetic - DNA carries genetic

information from between information from between

generationsgenerations

- monomers are nucleotides- monomers are nucleotides

- each monomer has a sugar, phosphate - each monomer has a sugar, phosphate group, group, and a base and a base (fig. 13)(fig. 13)

- four bases in DNA in different orders code for all - four bases in DNA in different orders code for all characteristics of life!characteristics of life!

- adenine, thymine, guanine, and cytosine - adenine, thymine, guanine, and cytosine (fig. (fig. 15)15)

- DNA is double helix- DNA is double helix

- hydrogen bonds hold- hydrogen bonds hold

it togetherit together

- DNA is found in nucleus- DNA is found in nucleus(fig. 14)(fig. 14)

- RNA is single stranded- RNA is single stranded

- DNA codes for RNA- DNA codes for RNA

- RNA carries genetic code- RNA carries genetic code

to cytoplasm where itto cytoplasm where it

codes for proteincodes for protein

synthesissynthesis