Chapter ThreeChapter Three

BIOCHEMISTRYBIOCHEMISTRY

Ch. 3 – sec 1Ch. 3 – sec 1

• 96.3% of the total weight of the human 96.3% of the total weight of the human body is made up of just four elements: body is made up of just four elements: carbon, nitrogen, oxygen and hydrogen.carbon, nitrogen, oxygen and hydrogen.

• All compounds classified into two groups:All compounds classified into two groups:• Organic CompoundsOrganic Compounds = Contain carbon. = Contain carbon.

• Most matter in living things that is not water, is made Most matter in living things that is not water, is made up of organic compounds.up of organic compounds.

• Inorganic CompoundsInorganic Compounds = Do not contain = Do not contain carbon.carbon.

• Example: Water!Example: Water!

Large Carbon MoleculesLarge Carbon Molecules• MonomersMonomers = The smaller compounds = The smaller compounds

which are joined together to form which are joined together to form polymerspolymers. . – Mono-Mono- means ________ means ________– Poly-Poly- means __________ means __________

• MacromoleculesMacromolecules = VERY large polymers = VERY large polymers– Macro-Macro- means means GIANTGIANT

• Carbohydrates, lipids, proteins, and nucleic acids are Carbohydrates, lipids, proteins, and nucleic acids are macromolecules. Sometimes these are also called macromolecules. Sometimes these are also called biomolecules. (molecules of life)biomolecules. (molecules of life)

• The molecules that are in all living cells!The molecules that are in all living cells!

Nucleic AcidsNucleic Acids

• Contain elements C, H, O, N, PContain elements C, H, O, N, P• Only two examples of nucleic acidsOnly two examples of nucleic acids

– DNA (Deoxyribose Nucleic Acid)DNA (Deoxyribose Nucleic Acid)– RNA (Ribose Nucleic Acid)RNA (Ribose Nucleic Acid)

• MonomerMonomer = Nucleotide = Nucleotide• What is in a Nucleotide?What is in a Nucleotide?

– Sugar (ring structure)Sugar (ring structure)– phosphatephosphate– nitrogen base nitrogen base

Nucleotide – the Nucleotide – the monomer (repeating monomer (repeating

unit) that builds to make unit) that builds to make DNADNA

DNA/RNA DNA/RNA FunctionFunction

• store and transmit hereditary store and transmit hereditary informationinformation

• codes for proteins -which determine codes for proteins -which determine traits (your genes)traits (your genes)

• DNA DNA RNA RNA Proteins Proteins

DNA structureDNA structure• Shape of Double Helix (twisted Shape of Double Helix (twisted

ladder)ladder)

• ““backbone” is alternating backbone” is alternating sugar/phosphate/sugar/phosphsugar/phosphate/sugar/phosphate/sugar…ate/sugar…

• ““rungs” are the nitrogen basesrungs” are the nitrogen bases– Exist in complementary PAIRS.Exist in complementary PAIRS.

– A (adenine) pairs with T A (adenine) pairs with T (thymine)(thymine)

– C (cytosine) pairs with G C (cytosine) pairs with G (guanine)(guanine)

ComplementaComplementary Base Pairsry Base Pairs

Can you Can you tell me the tell me the other half other half of the of the DNA?DNA?

““Code of Life”Code of Life”

• The order or sequence of the nitrogen bases The order or sequence of the nitrogen bases are different for every single living organism.are different for every single living organism.– More similar species will have more similar More similar species will have more similar

codes but not identicalcodes but not identical•Human vs. GorillaHuman vs. Gorilla

•Human vs. bacteriaHuman vs. bacteria

• The nitrogen bases are the “code”, which The nitrogen bases are the “code”, which instructs the cell which proteins to make and instructs the cell which proteins to make and makes all living organisms unique.makes all living organisms unique.

ProteinsProteins• Contain elements Contain elements

C, H, O, NC, H, O, N

• MonomerMonomer = amino acids = amino acids

(building block of (building block of proteins).proteins).

• There are 20 different amino There are 20 different amino acidsacids– Many different proteins Many different proteins

can be made depending on can be made depending on which amino acids which amino acids combine combine

– The sequence and number The sequence and number of amino acids = different of amino acids = different proteinsproteins

– Different proteins have Different proteins have different functionsdifferent functions

• Two amino acids can bond together Two amino acids can bond together with a “peptide bond” through with a “peptide bond” through condensation reactioncondensation reaction

• Polymers:Polymers:• Dipeptide – 2 amino acidsDipeptide – 2 amino acids• Polypeptide – many amino acids (long Polypeptide – many amino acids (long

chains)chains)

How are proteins made?How are proteins made?

• 1. DNA1. DNA

• 2. RNA2. RNA

• 3. Amino Acids 3. Amino Acids (the building (the building blocks)blocks)

• 4. Proteins4. Proteins

DNA RNA Amino Acid Protein Trait expression

All the different proteins have different jobs but all are responsible expressing your traits/genes that was directed by the DNA code (sequence of nitrogen

bases)

Protein Examples & Protein Examples & FunctionsFunctions

• Speed up reactions in cellsSpeed up reactions in cells

• Enzymes!!!!Enzymes!!!!– Lactase – breaks down sugar lactoseLactase – breaks down sugar lactose– Pepsin – breaks down proteins we eat Pepsin – breaks down proteins we eat

in stomachin stomach

StructuralStructuralKeratin, Elastin, CollagenKeratin, Elastin, Collagen

Can find protein in skin, hair, nails, hornsCan find protein in skin, hair, nails, horns

StorageStorageCasein (found in milk)Casein (found in milk)

Ovalbumin (found in egg whites)Ovalbumin (found in egg whites)

HormonesHormonesInsulin (regulates blood sugar level)Insulin (regulates blood sugar level)

Transport- movementTransport- movementActin and Myosin (contractions in muscles)Actin and Myosin (contractions in muscles)Hemoglobin (transports oxygen in blood)Hemoglobin (transports oxygen in blood)

Structure of an amino Structure of an amino acidacid

CarbohydratesCarbohydrates

• Carbohydrates contain Carbohydrates contain C, H, O.C, H, O.• Monomers Monomers

– Monosaccharide (one sugar)Monosaccharide (one sugar)– Simple sugarsSimple sugars– GLUCOSE!!GLUCOSE!!

CarbohydratesCarbohydrates

• 2 monosaccharides (monomers) 2 monosaccharides (monomers) bonded together will make a bonded together will make a disaccharidedisaccharide– Small polymerSmall polymer– Still considered a “simple sugar”Still considered a “simple sugar”– SucroseSucrose– LactoseLactose– MaltoseMaltose

CarbohydratesCarbohydrates• Many monosaccharide Many monosaccharide

bonded together will bonded together will make a polysaccharide.make a polysaccharide.– Large polymerLarge polymer– Complex sugarsComplex sugars

• Polysaccharides are how Polysaccharides are how organisms store extra organisms store extra

sugarsugar– CelluloseCellulose– GlycogenGlycogen– STARCHSTARCH

Cellulose is a complex sugar that provide structure for plants!

Carbohydrate Carbohydrate FunctionFunction

• Main source of immediate fuel! Main source of immediate fuel! – ““Life runs on sugar”Life runs on sugar”

• Provides ENERGY (ATP) needed for Provides ENERGY (ATP) needed for cell metabolism.cell metabolism.

• Short term energy.Short term energy.

Structure of Structure of carbohydratescarbohydrates

“ring structures”“ring structures”

LipidsLipids• ““Fats”Fats”• Contain elements C, H, O, and sometimes Contain elements C, H, O, and sometimes

PP– Really depends on what type of lipid.Really depends on what type of lipid.

• Lipids are long chains of fatty acids and Lipids are long chains of fatty acids and glycerol.glycerol.

• Lipids are NONPOLAR = do not dissolve in Lipids are NONPOLAR = do not dissolve in water (hydrophobic)water (hydrophobic)

FunctionFunction

Composes CELL (plasma) membrane Composes CELL (plasma) membrane Used as chemical messengersUsed as chemical messengersReserve storage of energyReserve storage of energyLong term energyLong term energy

Lipid ExamplesLipid Examples• Phospholipids

– Cell membranes

• Triglycerides

• Steroids– Cholesterol– Hormones

•Testosterone•Progesterone•Estrogen•Adrenocorticoid

• Oils, butter, lard• Wax

– Animals, plant leaves, bee, carnauba, etc.

• Saturated FatsSaturated Fats = solid at room temp. = solid at room temp. – Ex. butter, lard, animal fat. Ex. butter, lard, animal fat.

• Unsaturated FatsUnsaturated Fats = Liquid at room temperature. = Liquid at room temperature.– Ex. oils, etcEx. oils, etc

Diets that are high in fats

(lipids) increase

chances of cardiovascula

r disease.

Structure = long chains!!!!

Where does your all Where does your all energy come from?energy come from?

Your cells utilize which one first?

How are all the 4 How are all the 4 macromolecules connected? macromolecules connected?

(The highlights)(The highlights)• Lipids construct the Lipids construct the cell membranecell membrane and also and also

contribute to cell metabolism (reserve energy).contribute to cell metabolism (reserve energy).– Wouldn’t have cells without phospholipids membrane! Wouldn’t have cells without phospholipids membrane!

• Nucleic Acids provide the genetic code (hereditary info) Nucleic Acids provide the genetic code (hereditary info) that directs the cellthat directs the cell– Instructions to make specific proteins. Instructions to make specific proteins.

• Different proteins go and perform their specific jobDifferent proteins go and perform their specific job– movement, defense, speed up reactions, trait expression, etc.movement, defense, speed up reactions, trait expression, etc.

– DNA DNA RNA RNA Protein Protein

• Carbohydrates provide primary energy to fuel all cell Carbohydrates provide primary energy to fuel all cell reactions (METABOLISM!)reactions (METABOLISM!)