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Macromolecules The Molecules of Life!

Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

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Page 1: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Macromolecules

The Molecules of Life!

Page 2: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Most macromolecules are polymers

Monomer

Polymer

Macromolecule

Page 3: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Polymerization Reactions

Chemical reactions that link two or more small molecules to form larger molecules

Page 4: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Condensation Reactions

Also known as dehydration synthesis

Monomers are linked covalently producing a net removal of water.

One monomer loses an H the other an OH or hydroxyl.

Requires energy and enzymes

Page 5: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Hydrolysis

“Water breaking”A reaction that breaks the

covalent bonds between monomers by the addition of water molecules

Page 6: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Structural variation

Structural variation of macro-molecules is the basis for the enormous diversity of life.

Unity= only about 40-50 monomersDiversity- new properties emerge as

various monomers are put together

Page 7: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Carbohydrates

Quick energyMade from monomers called

monosaccharideClassified on the number of

simple sugars

Page 8: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

MonosaccharideSimple sugars

Ratio = CH2O

Major nutrients for cell –glucoseCan be made by the sun

PhotosynthesisEnergy stored in their chemical bonds

which are broken in cell respirationCarbon skeletons used for other organic

molecules.

Page 9: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Characteristics of sugar

An OH- group is attached to each carbon except one which is double bonded to a carbonyl

Size of skeleton varies 3 to 7 carbons

Spatial arrangements vary

Page 10: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

3 Monosaccharide

Glucose

Fructose

Galactose

Page 11: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Disaccharides

“Double sugar”Two monosaccharides joined by

a GLYCOSIDIC linkage.A covalent bond between two

sugar monomers resulting from a condensation reaction.

Page 12: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Examples of Disacchrides

Maltose glucose + glucose= malt sugar

Lactose glucose + galactose= milk sugar

Sucrose glucose + fructose= fruit sugar

Page 13: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Polysacchrides

Macromolecules that are polymers of a few hundred or thousand monosaccharides

2 important biological functionsEnergy storage- starch/glycogenStructural support- cellulose/chitin

Page 14: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Starch

Energy storage for plantsHelical glucose polymer with alpha

helix 1-4 glycosidic linkages. Stored in plastidsAmylose- simplest formMost animals can digest

Page 15: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Glycogen

Storage polysaccharide in animals

Stored in the muscle and live of humans and other vertebrates

Page 16: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Structural Polysaccharides

Cellulose- Linear unbranched polymer of D-glucose in Beta 1-4 linkages.

Major component of cell walls/ reinforcesDifferent from starch in its glycosidic

linkages! (important!)Cannot be digested by most organisms.Exception- some bacteria, fungi.

Page 17: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Chitin

A polymer of an amino sugar

Forms exoskeletons of arthropods

Page 18: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Lipids

Fats, Phospholipids and SterolsInsoluble in water but will

dissolve in nonpolar solvents like ether, chloroform benzene

Page 19: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

FATS composed of C,H,O

Macromolecules made from:1. Glycerol- a 3-carbon alcohol

2. Fatty Acid (carboxylic acid) A carboxyl group at one end and a

attached (non polar) hydrocarbon tail

Page 20: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Ester Linkage

Bond formed between a hydroxyl group (OH-) and a carboxyl group (-COOH)

Triacylglycerol- a fat composed of three fatty acids bonded to one glycerol by 3 ester linkages.

SEE BOOK for pictures!!!

Page 21: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Characteristics of fat

Insoluble in water due to long fatty acid chains which have lots of nonpolar C-H bonds

Vary by fatty acid composition, length, and location of Carbon to Carbon bonds.

Page 22: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Saturated Fat

No double bonds, Carbon bonded to maximum # of hydrogen's

Solid at room tempMost animal fats

Page 23: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Unsaturated Fats

One or more double bonds between carbons in fatty acid tail

Tail kinks at each C=C so molecules do not pack close enough to solidify.

Liquid, plant fats

Page 24: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Why is Fat important?

Energy storage- 1 gram of fat has 2x the energy as a gram of polysaccharide

More compact fuel reservoir than a carbohydrate

Cushions vital organsInsulates against heat loss

Page 25: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Phospholipids

Compound make up of a glycerol, two fatty acids and a phosphate

The head is hydrophilic The tails are hydrophobic

Page 26: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Importance of Phospholipids

Major constituents of cell membranes. Because phospholipids are ambivalent towards water. they are able to form a type of barrier around the cell’s cytoplasm.

Page 27: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Steroids

Lipids which have four fused carbon rings with various functional groups attached.

See picture in book

Page 28: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Cholesterol- an important steroid

Precursor to many other steroid including

Vertebrate sex hormonesHas an important role in the keeping the

cell membrane fluidOverproduction and over consumption

can contribute to atherosclerosis

Page 29: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Proteins

Composed of Carbon, Hydrogen, OxygenAnd Nitrogen

Page 30: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Proteins are building blocks

The monomers are amino acids. There are 20 amino acids which form a

huge variety of proteinsPolypeptide chains- polymers of amino

acids arranged in a specific linear sequence and linked by peptide bonds.

Page 31: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Protein

A macromolecule that consists of one or more polypeptide chains folded and coiled into specific conformations.

Each kind has its own unique 3-D shape

Page 32: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Importance of Proteins

Structural support (collagen) Storage (of amino acids) Transport (hemoglobin) Signaling (Chemical messengers) Cellular response to chemical stimuli Movement (contractile proteins) Defense (antibodies) Catalysis of Biochemical reactions Enzmyes

Page 33: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Amino Acids

Building block of proteinMost consist of an asymmetric carbon

covalently bonded to: H OHydrogen atom H3N+- C

Carboxyl group R OAmino groupVariable R group (side chain)

Page 34: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Unique properties of Amino Acids

A. acids contain both a carboxyl group and an Amino group. Since one group acts like a weak acid (carboxyl) (-) the other acts as a weak base (amine) (+) so an amino acid can exist in three anion states.

Some have polar side groups, some nonpolar.

Page 35: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Peptide Bond

Covalent Bond formed by a condensation reaction that links the carboxyl group of one amino acid to the amino group of another.

Has polarity with the –COOH group on one end and the NH2 group on the other

Backbone= N-C-C-N-C-C-

Page 36: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

A Proteins Shape

3-D unique shapeNative conformationEnables a protein to recognize and bind

specifically to another moleculeConsequence of linear arrangement of

amino acids, folded and coiled and stabilized by chemical bonds and weak interactions.

Page 37: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Four levels of Protein Structure

PrimarySecondary

TertiaryQuaternary

Page 38: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Primary

Unique sequence of amino acids(Like beads on a string)Pioneer in sequencing- Frederick

Sanger who sequenced insulin in the late 40’s.

Page 39: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Secondary

Regular repeated coiling and folding of a protein’s polypeptide backbone

Contributes to proteins overall conformation

Stablized by HYDROGEN bonds between peptide linkages

2 Types: Alpha Helix and Beta Pleated See book pictures

Page 40: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Tertiary Structure (important!)

Irregular contortions of a protien due to bonding between side chains ® groups; third level of protein structure imposed on primary and secondary structure.

Covalent linkage( disulfide bridges) and weak interactions (ionic bonds, hydrogen bonds and hydrophobic interactions) contribute to bonding stability.

Page 41: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Quaternary Structure

Structure that results from the interaction among several polypeptides in a single protein

Example: Collagen, HemoglobinSee the book for a picture

Page 42: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

What determines protein conformation?

A protein’s 3-D shape is the result of the interactions responsible for the secondary and tertiary sturcture

Influenced by physical and chemical environmental conditions

If altered may become DENATURED and lose its native conformation

Page 43: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Denaturation

A proteins shape can be altered by:Transfer to an organic solvent. Chemical agents that disrupt hydrogen

bonds, ionic bonds and disulfide bridgesExcessive heat

Some can return to their original state.

Page 44: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

A proteins shape..

Even though the primary structure determines the proteins conformation, many other factors affect the final shape which can not always be determined ahead of time.

Page 45: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Nucleic Acids

Protein structure is determined by primary structure which is determined by GENES- heredity units that consist of DNA- a type of nucleic acid

There are two types: DNA and RNA

Page 46: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

DNA characteristics

Contains coded information that programs ALL cell activity

Contains directions for its own replication Is copied and passed from one generation to

the next In eukaryotic cells found primary in the

nucleus Makes up genes that code for Protein

Synthesis

Page 47: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

RNA characteristics

Functions in the actual synthesis of proteins

Sits of synthesis are on ribosomes in the cytoplasm

Messenger RNA carries the encoded genetic message from the nucleus to the cytoplasm

DNA---RNA---Protein

Page 48: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

What makes up a nucleic acid?

Monomers are nucleotides linked together by condensation synthesis.

A nucleotide is: 1. nitrogenous base (A,T,C,G,U)2. a five carbon sugar (Pentose)3. A phosphate group

Page 49: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

The bases

Pyrimidine= nitrogenous base with a six- membered ring made up of carbon and nitrogen atoms

Cytosine, Thymine (DNA), Uracil (RNA)Purine- nitrogenous base with a 5-

membered ring fused to a six-membered ring:

Adenine and Guanine

Page 50: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

Functions of nucleotides

Monomers of nucleic acidsTransfer energy from one molecule to

another. (ATP)Are electron acceptors in enzyme

controlled redox reactions (NAD)

Page 51: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

The structure of DNA

Double helixBackbone of Sugar and phosphate. The

backbone is the result of phosphodiester linkages between the phosphate of one nucleotide and the sugar of the next.

The sugar is deoxyriboseThe bases in DNA are A,T,C,G

Page 52: Macromolecules The Molecules of Life!. Most macromolecules are polymers Monomer Polymer Macromolecule

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