1

““MacromolecMacromoleculesules

of Life”of Life”

ppt adapted from cmassengale

2

Organic Organic CompoundsCompounds

• CompoundsCompounds that contain CARBONCARBON are called organicorganic.

• MacromoleculesMacromolecules are large moleculesolecules.

• Organic Macromolecules

has C-C bonds large molecules

3

Organic Organic CompoundsCompoundsCarbon (C)Carbon (C)• CarbonCarbon has 4 electrons4 electrons in

outer shell.

• CarbonCarbon can form covalent covalent bondsbonds with as many as 4 4 other atoms (elements).

• Usually with C, H, O or NC, H, O or N.

• Example:Example: CHCH44(methane)(methane)

Organic CompoundsOrganic CompoundsCarbon (C)Carbon (C)

• What does sharing electrons with other atoms, in four covalent bonds mean?

• Each carbon acts as an ‘intersection’

with 4 different branch points

• Creates endless variety of (organic) carbon molecules

4Vary in length

Diversity of Carbon-Based Molecules

Unbranched or branchedRings

Different location of double bonds

6

Macromolecules of Macromolecules of LifeLife

• Large organic molecules.Large organic molecules.• Also called POLYMERSPOLYMERS.• Made up of smaller “building

blocks” called MONOMERSMONOMERS.• Biological macromoleculesBiological macromolecules

1. Carbohydrates1. Carbohydrates2. Lipids2. Lipids3. Proteins3. Proteins4. Nucleic acids (DNA and 4. Nucleic acids (DNA and

RNA)RNA)

7

CarbohydratesCarbohydrates“How Sweet it “How Sweet it

is”is”

glucoseglucoseglucoseglucose

8

CarbohydratesCarbohydrates• SIZESIZE

– small small to largelarge• TypesTypes

AA.. monosaccharide (sugars)monosaccharide (sugars)B.B. disaccharide (sugars)disaccharide (sugars)

C.C. polysaccharide polysaccharide (starches)(starches)

glucoseglucose

glucoseglucoseglucoseglucose

glucoseglucoseglucoseglucose

glucoseglucoseglucoseglucose

glucoseglucoseglucoseglucose

cellulosecellulose

Carbohydrates• Monomer = sugar = “saccharide”• Structure:

– Small (simple) sugar molecules

•Examples?–Monosaccharides

» glucose, fructose» galactose, deoxyribose

–Disaccharides»SucrSucroseose (glucose+fructose) (glucose+fructose)»LactLactose (glucose+galactose) (glucose+galactose)»MaltMaltoseose (glucose+glucose) (glucose+glucose)

• Monomer = “saccharide”• Structure:

– Large molecules– Long chain of many single sugar units

hooked together

•Examples?–Polysaccharides

» Starches…(Pasta, bread, potatoes)»Cellulose … (lettuce, corn) provides

structure for plant cell walls

»Glycogen … (stored in liver, muscle cells break down glycogen to release glucose when needed for energy) 10

Carbohydrates

Carbohydrate Function• Functions

– Main source of energy for living things•gasoline for cells (ATP)

– Monosaccharides = immediate E – Polysaccharides = longer term E– Plants store carbs as cellulose—gives

their cells strength– Animals store carbs as glycogen

12

LipidsLipids“Greasy “Greasy

Molecules”Molecules”

copyright cmassengale

13

LipidsLipids• Hydrophobic= Hydrophobic= water hatingwater hating• Hydrophillic= Hydrophillic= water lovingwater loving

• Lipids =general term for compounds which are not soluble in waternot soluble in water.

• Lipids are soluble in other solventsare soluble in other solvents.

• Examples:Examples:1. Fats – from animals 1. Fats – from animals

(butter,lard,margarine)(butter,lard,margarine)

2. Oils-from plants 2. Oils-from plants (canola oil, olive oil, corn (canola oil, olive oil, corn

oil)oil)

3. Phospholipids 3. Phospholipids (cell (cell membranes)membranes)

4. Waxes 4. Waxes (bees wax, ear wax)(bees wax, ear wax)

5. Steroid hormones5. Steroid hormones6. Triglycerides6. Triglycerides

copyright cmassengale 14

LipidsLipids

15

LipidsLipidsSix functions of lipids:Six functions of lipids:

1.1.“stores the most energy”“stores the most energy”Long term Long term energy storageenergy storage

2.2. Protection against heat loss Protection against heat loss ((insulationinsulation))3.3. Protection against physical shock Protection against physical shock (cushioning)(cushioning)4.4. Protection against water loss Protection against water loss (hydrophobic)(hydrophobic)5.5. Chemical messengers (hormones)Chemical messengers (hormones)6.6. Major component of membranes Major component of membranes

(phospholipids)(phospholipids)

16

LipidsLipidsTechnically called? TriglyceridesTechnically called? Triglycerides

CompositionComposition:(1) glycerol:(1) glycerol and (3) fatty 3) fatty acidsacids.

H

H-C----O

H-C----O

H-C----O

H

O

C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3

=

O

C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3

=

O

C-CH2-CH2-CH2-CH =CH-CH2 -CH

2 -CH2 -CH

2 -CH3

=

Glycero

l

Fatty Acids

saturated

saturated

unsaturated

17

Fatty AcidsFatty AcidsTwo kinds of fatty acidsfatty acids you may see on food labels:

1.1. Saturated fatty acids:Saturated fatty acids: no double bonds no double bonds (())

solids at room temperaturesolids at room temperature

2.2. Unsaturated fatty acids:Unsaturated fatty acids: double bonds double bonds (())

liquids at room temperatureliquids at room temperature

O

C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3

=

saturatedsaturated

O

C-CH2-CH2-CH2-CH= CH-CH2 -CH

2 -CH2 -CH

2 -CH3

=unsaturated

18

ProteinsProteins“Amazing “Amazing Variety”Variety”

19

• Amino acids – building blocks – monomer– (20 different kinds of aa) bonded together by peptide peptide

bondsbonds (polypeptidespolypeptides).

– Each a.a. made of….• Central CARBON bonded to…

– Amino group (NH2)– Carboxyl Group (COOH)– Hydrogen– “R” group

Proteins Proteins (Polypeptides)(Polypeptides)

Amino group

Carboxyl group

Examples of 2 different amino acids and their side groups

copyright cmassengale 20

21

Proteins Proteins (Polypeptides)(Polypeptides)Six functions of proteins:Six functions of proteins:

1.1.Immune/Defense:Immune/Defense: Kill invaders Kill invaders (Antibodies)(Antibodies)

2.Transport: 2.Transport: Blood Blood (hemoglobin), (hemoglobin),

Cell membrane proteinsCell membrane proteins3.Regulatory:3.Regulatory:hormoneshormones4.Movement:4.Movement: muscles muscles (Actin,Myosin)(Actin,Myosin)

5.Structural:5.Structural: Hair,horns,feathers Hair,horns,feathers (Keratin)(Keratin)

Skin Skin (Collagen). (Collagen).

Bones,Tendons, Bones,Tendons, Ligaments, Ligaments, Cartilage Cartilage (Connective (Connective Fibers) Fibers)

6.Regulatory:6.Regulatory:help control cellular help control cellular reactionsreactions

(Enzymes…-ase)(Enzymes…-ase)

22

Proteins Proteins (Polypeptides)(Polypeptides)

Four levels of protein Four levels of protein structure:structure:

A.A. Primary StructurePrimary Structure

B.B. Secondary Structure Secondary Structure

C.C. Tertiary Structure Tertiary Structure

D.D. Quaternary Structure Quaternary Structure

Primary StructurePrimary Structure• Amino Acids linked (bonded) in a STRAIGHT CHAIN

23

aa1 aa2 aa3 aa4 aa5 aa6

Peptide Bonds

Amino Acids (aa)

24

Secondary StructureSecondary Structure

• 3-dimensional folding arrangement of a primary primary structurestructure into coilscoils and pleatspleats held together by hydrogen bondshydrogen bonds.

• Two examples:Two examples:

Alpha HelixAlpha Helix

Beta Pleated SheetBeta Pleated Sheet

Hydrogen BondsHydrogen Bonds

25

Tertiary StructureTertiary Structure• Secondary structuresSecondary structures bentbent and

foldedfolded into a more complex 3-D more complex 3-D arrangementarrangement of linked polypeptides

• Bonds: H-bonds, ionic, disulfide Bonds: H-bonds, ionic, disulfide bridges (S-S)bridges (S-S)

• Call a “subunit”.“subunit”.

Alpha HelixAlpha Helix

Beta Pleated SheetBeta Pleated Sheet

26

Quaternary Quaternary StructureStructure

•Composed of 2 or more “subunits”•Globular in shape•Form in Aqueous environments•Example: enzymes (hemoglobin)enzymes (hemoglobin)

subunitssubunits

Protein Structure - Quiz

copyright cmassengale 27

28

Nucleic Nucleic AcidsAcids

copyright cmassengale

29

Nucleic acidsNucleic acids• Two types:Two types:

a. Deoxyribonucleic acid a. Deoxyribonucleic acid ((DNADNA-- double helix) double helix) b. Ribonucleic acid (b. Ribonucleic acid (RNARNA-single -single strand) strand)

• Nucleic acids Nucleic acids are composed of long chains of nucleotidesnucleotides…building blocks…monomer

copyright cmassengale

30

Nucleic acidsNucleic acids• Nucleotides include:Nucleotides include:

– phosphate groupphosphate group– pentose sugar (5-carbon)pentose sugar (5-carbon)– nitrogenous bases:nitrogenous bases:

DNADNA RNARNA

adenine (A)adenine (A) adenine (A)adenine (A)thymine (T) thymine (T) uracil uracil

(U)(U)cytosine (C)cytosine (C) cytosine (C)cytosine (C)guanine (G)guanine (G) guanine (G)guanine (G)

31

NucleotideNucleotide

OO=P-O O

PhosphatePhosphate GroupGroup

N

Nitrogen Nitrogen BaseBase(A, G, C, T or U)(A, G, C, T or U)CH2

O

C1C4

C3 C2

5

SugarSugar(deoxyribose)(deoxyribose)

32

DNA - double helixDNA - double helix

P

P

P

O

O

O

1

23

4

5

5

3

3

5

P

P

PO

O

O

1

2 3

4

5

5

3

5

3

G C

T A

copyright cmassengale

33

DNA- Gene for Baldness

Build a DNA molecule