What are organic molecules?

Molecules of Life

What are biological molecules?

Compounds that contain carbon

Carbohydrates Lipids Proteins Nucleic Acids

Organic Molecules

What is a cell made up of mostly?

Mostly water, but what else?

Carbon based molecules

Why is carbon so significant for these molecules?

Recall that an atom’s bonding ability

• Is related to the number of electrons it must share to complete its outer shell

Atomic number?

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

Vary in length

Diversity of Carbon-Based Molecules

Activity: Diversity of Carbon-Based Molecules http://wps.aw.com/bc_campbell_essentials_3/0,11844,3107816-,00.html

Unbranched or branchedRings

Different location of double bonds

Methane Is a hydrocarbon

What is a hydrocarbon?

………..Carbon

& Hydrogen

Methane is the simplest

Examples of larger hydrocarbons??

Octane (in gasoline)

Fatty foods

Biological Molecules

‘Carbs’

Oils

Food

DNARNA

SugarGlucoseGlycogenCellulose

Fatty acids(sat & unsat)Butter

StructuralStorageEnzymesAntibodies

Carbohydrates

Small (simple) sugar molecules

What type of sugar is found in the following?

Long starch molecules in pasta, potatoes

These are our primary sources of dietary energyIn plants, carbs used as building material

Examples?

Examples?

Monosaccharides

Polysaccharides

Glucose Fructose

Starch Cellulose

DisaccharidesLactose Sucrose

Monosaccharides

What type of sugar is found a sports drink?

Glucose

What type of sugar is found in fruit?

Fructose

What about honey?

Its really sweet? Why?

It contains both glucose and fructose

Glucose and FructoseHave the same formula… C6H12O6

Why are they ‘different’?

They are isomers

L-Dopa

Form rings in aqueous solutions

Which sugar is this?

Why are the carbons numbered?

Glucose

DisaccharidesAre ‘double sugars’

What are they constructed from?

Disaccharides

2 monosaccharides

Disaccharides

Sucrose:

Maltose: glucose and

galactose andLactose:

glucose and

glucose

glucose

fructose

Lactose, another disaccharide

• Its a condition called lactose intolerance

• Some people have trouble digesting lactose

• Missing gene for lactase enzyme

Sucrose The most common disaccharide is sucrose, what do you know it as?

Common table sugar

Sugar cane

What plants do we use to extract table sugar?

Roots of sugar beets

PolysaccharidesAre long chains of sugar units

(polymers) (monosaccharides)

Polysaccharides

What are some polysaccharides?

StarchGlycogen

Cellulose

Starch

Glycogen

Cellulose

Potatoes and grains are major sources of starch in the human diet

Liver, muscle cells break down glycogen to release glucose when needed for energy

Structural component, dietary fiber

Describe some characteristics of the following:

CarbohydratesBiological Macromolecule:

Function: • Dietary energy Monomer:

Examples:

• Disaccharides

• Storage• Plant structure

• Monosaccharides

• Polysaccharides

(simple sugars)

(double sugars)

(long polymers)

(glucose, fructose)

(maltose, lactose, sucrose)

(starch, glycogen, cellulose)

Lipids

Butter, lard, margarine, and salad oil

Do these lipids mix well with water?

Fats

Activity: Lipids

http://wps.aw.com/bc_campbell_essentials_3/0,11844,3107816-,00.html

LipidsThis diverse group of molecules includes?

Fatty acids

Characterized by a carbon skeleton consisting of four rings with various functional groups attached

A biological compound consisting of three fatty acids linked to one glycerol molecule

Steroids

(energy storage, cushioning, insulation)

(cholesterol, in membranes)

Fatty AcidsTechnically called? triglycerides

Glycerol

A fat molecule:

‘saturated’

‘unsaturated’

3 Fatty acids

Double bond ‘unsaturated”

Unsaturated fatty acids

Have less than the maximum number of hydrogens bonded to the carbons

Saturated fatty acids

Have the maximum number of hydrogens bonded to the carbons

(plant oils)

(butter)

Double Bonds

• Saturated fats are solid at room temperature

• Unsaturated fats tend to be liquids at room temperature

What is the significance of the number of double bonds in the hydrocarbon tails?

Saturated fats in the diet can lead to heart disease

unsaturated fats are safer

vegetable oils Example?

Example? butter and lard

Impact on health?

Impact on health?

Steroids

How does the structure differ from fatty acids?

Ring structure, various functional groups

How does the function differ from fatty acids?

Functional groups affect function

Example? • causes differences between the hormones estrogen and testosterone

(anatomical and physical development)

• cholesterol in membranes

Biological Macromolecule:

Function: Monomer:

Examples:

Lipids

• Long term energy storage• Hormones

• Fats, oils

• Steroids

(triglycerides) (butter, lard, margarine, salad ols)

(lipid rings) (cholesterol, hormones)

Proteins

• A three-dimensional biological polymer

Activity: Protein Functions

http://wps.aw.com/bc_campbell_essentials_3/0,11844,3107816-,00.html

Activity: Protein Structure

What is a protein?

• Constructed from a set of 20 different monomers

• Monomers are amino acids

Structural Proteins

Storage Proteins

Contractile Proteins

Transport Proteins

Defensive Proteins

Receptor Proteins

Enzymes

Signal Proteins

Sensory Proteins

Gene Regulatory Proteins

Activity: Protein Functions Activity: Protein Structure

http://wps.aw.com/bc_campbell_essentials_3/0,11844,3107816-,00.html

Structure, Function

Structural

1. Hair, silk of spidersStorageContractileTransportDefenseReceptorEnzymesSignalSensoryGene regulatory

2. Antibodies3. Detect environmental changes4. Change rate of a reaction5. Control genes6. Cell communication7. Trigger changes inside cell8. Carry molecules from place to place9. Stockpile building materials

10. Can move parts of a cell or animal

The Monomers

What does each amino acid monomer consist of?

A central carbon atom

Bonded to four covalent partners

Amino group

Carboxyl group

Each side group is unique Identifies each amino

acid’s characteristics

Examples of 2 different amino acids and their side groups

Structure Proteins are complex!

To simplify, we’ll describe them in terms of 4 levels of structure:

Primary

Secondary

Tertiary

Quaternary

– a particular # and sequence of amino acids

– turns and folds, alpha helix, pleated sheet

– irregular loops and folds, 3-D shape

– 2 or more polypeptides combined

What do they look like?

Primary structure

Quaternary structure Secondary structure

Tertiary structure

Biological Macromolecule:

Function: Monomer:

Examples:

Proteins

• Many!• Change rate of reaction• Carry molecules• Cell communication

Amino group

Carboxyl group

• Enzyme (lactase)

• Transport (hemoglobin)

• Defense (antibodies)

= 20 amino acids

Nucleic AcidsWhat are nucleic acids?

The cells information storage molecules

• There are two types of nucleic acids

DNA, deoxyribonucleic acidRNA, ribonucleic acid

• These ‘work together’ to synthesize protein

Activity: Nucleic Acid Functions

Synthesizing Protein

It carries instructions for building all the proteins

What does DNA do?

Information in DNA is transcribed into RNA

What does DNA do?

RNA acts as an intermediary in the protein-making process

What does RNA do?

DNA

RNA

Protein

What else does RNA do?

RNA then translates the (transcribed) information into the primary structure of proteins

What is the primary structure of proteins?

What does protein do?

Proteins carry out cell activities

Structure What is the structure of nucleic acids?

They are polymers of nucleotides

Phosphate group

What do the nucleotides contain?

Sugar

Nitrogen base

(Deoxyribose)

What do DNA nucleotides contain?

Each DNA nucleotide has one of the following bases:

Adenine (A)

Guanine (G)

Thymine (T)

Cytosine (C)

12

34

Which one is which?

Match the numbers to the base

Polymers of nucleotidesLinked into long chains

Called polynucleotides or DNA strands

A sugar-phosphate backbone joins them together

Nucleotide

Bases

Activity: Nucleic Acid Structure

2 DNA strands form

helixHow does this happen?

Via complementary binding

C always binds with G

A always binds with T

(and hydrogen bonding)

RNA, different from DNA

The RNA sugar has 2 OH groups vs 1 in DNA

It has the base uracil (U) instead of thymine (T) in DNA

(Ribose vs deoxyribose)

Biological Macromolecule:

Function: Monomer:

Examples:

Nucleic Acids

• Information storage

• DNA• RNA

Phosphate

BaseSugar

Could this be a monomer for RNA?

Chapter 3: The Molecules of LifeActivities Quiz

http://wps.aw.com/bc_campbell_essentials_3/0,11844,3107816-,00.html

Which of these is a source of lactose?

If a DNA double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain?

Sugar beets

25,

milk potatoes sugar cane starch

150, 50, 75, 200

Which of these is a polysaccharide?

Sucrose,

Defensive proteins are manufactured by the _____ system.

Immune,

Which of these illustrates the secondary structure of a protein?

A B C D E

glucose, galactose, celluloselactose,

nervous, cardiovasculardigestive, integumentary,

Matching: vocabulary definitions

RNAGenePolymerProteinDouble helixAmino acidNucleotidesPolypeptideDNA

_____

_____

_____

1. A double-stranded, helical nucleic acid molecule capable of replicating and determining the

inherited structure of a cell’s proteins.

2. A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous

bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.

3. An organic molecule possessing both carboxyl and amino groups. Amino acids serve as the monomers of proteins

4. The building block of a nucleic acid, consisting of a five-carbon sugar covalently bonded to a

nitrogenous base and a phosphate group

_____

_____5. A three-dimensional biological polymer constructed from a set of 20 different monomers called amino acids

_____ 6. A polymer (chain) of many amino acids linked together by peptide bonds

_____ 7. A long molecule consisting of many similar or identical monomers linked together

_____ 8. The form of native DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape.

_____9. A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).