…so what is the what you eat made of?

You are what you eat…

The Four Organic MoleculesEssential Questions:

What is “Organic?”

What are the 4 major Organic Compounds?

How are they made?

What are they used for?

Organic Molecules make up all organisms

http://www.youtube.com/watch?v=ypbb9Zi5Tao (0:40 -2:14)

What does “Organic” Mean?In Biology, organic means “relating to organisms.”

(NOT food grown without the use of pesticides, antibiotics, or other industrial chemicals)

All organic molecules contain

covalently bonded Carbon.

What does “Organic” Mean?

Carbon cycles through all living things through the processes of photosynthesis, cellular respiration, death, and decomposition.

We’ll talk more about the Carbon Cycle in a few weeks!

• Carbon can bond to other carbon atoms, which gives carbon the ability to form chains that are almost unlimited in length.

• These carbon-carbon bonds can be single, double, or triple.

• The chains can be straight, branched, or even ring-shaped.

• Therefore, carbon is unique in that it can form millions of different large and complex structures.

http://www.youtube.com/watch?v=cOJ3MUpDrfI (0-1:20)

Why Carbon is so Awesome...

How many bonds/shared electrons can a Carbon atom make?

How are the Four Organic Macromolecules Formed?

Dehydration synthesis: joins molecules by removing a molecule of water.

Hydrolysis: breaks apart molecules by adding water (the opposite process)

Polymerization: small units (monomers) are joined together to form large units (polymers.)

What are the four organic molecules?

Lipids

Proteins

Carbohydrates

Nucleic Acids

What is in a cheeseburger?

Nutrition Facts (Big ‘N Tasty at McDonalds):

Total Fat: 29 grams

Saturated Fat: 9 grams

Carbohydrates: 41 grams

Protein: 24 grams

Carbohydrates

Which part of the cheeseburger has the most carbohydrates?

Carbohydrates• Composed of Carbon, Hydrogen and Oxygen in a 1:2:1 Ratio.• Used for short term energy storage (quick energy!) and structural

support• Ending “-ose” = sugar

How many sugars? Examples

1 sugar Monosaccharide Monomer Plants: glucose fructose Animals: galactose (milk)

2 sugars Disaccharide Polymer Plants: sucrose, maltoseAnimals: lactose (milk)

3+ sugars Polysaccharide Polymer Plants: starch, cellulose Animals: glycogen

Glucose

Why Carbohydrates?

• Many animals store extra sugar as glycogen.– Glycogen stored in your muscles supplies energy for

movement. – Glycogen stored in your liver is released when the

glucose (sugar) in your blood runs low.• Recall: What is this an example of?

– Homeostasis!

• Plants store excess sugar as starch.

• Plants also make cellulose, a strong, rigid fiber used for support.

Why does the bun have carbohydrates?

How do plants get the carbon they needs to form these carbohydrates?

Why does the bun have carbohydrates?

How do plants get the carbon they needs to form these carbohydrates?

Why does the bun have carbohydrates?

What other part of the Big N’ Tasty is composed of

carbohydrates?

What other part of the Big N’ Tasty is composed of

carbohydrates?

Cellulose!

Which part of the cheeseburger is the best

source of protein?

ProteinsProteins are present in every cell, tissue and organ in our bodies.

These proteins are constantly being broken down and replaced.

Composed of Carbon, Hydrogen, Oxygen, Nitrogen, and Sulfur

Provide structure for:cells, bones, muscles, tissues, organs, hormones…most everything in the body!

Special Function: Proteins are responsible for cell metabolism (via enzymes)

ProteinsThe protein in the food we eat is digested (broken down) into amino acids that are later used to build and replace other proteins in our bodies.

Monomers = amino acidsPolymers = proteins

When the amino acids join, they form a polymer called a polypeptide.

The monomers in an amino acid are held together by peptide bonds.

Proteins can be destroyed by extreme heat (fever) = denature

Protein Structure

Amino acids are the building blocks of proteins.

There are 20 essential amino acids

All amino acids have the same Amino group and carboxyl groups, but each amino acid has its own unique R- group. Only 20 amino acids can combine in different arrangements

to form all of the many different kinds of proteins in our bodies!

Shape is very important; if a protein is not the right shape, it will not work or only have partial function!

Why does the meat have so much protein?

Which part of the cheeseburger is a source

of fat?

What is fat?• Fats are a type of lipid.• Lipids are hydrophobic

(water-fearing) organic molecule including fats, oils, waxes, phospholipids and steroids.

Lipids

Monomers: 1 glycerol & 3 fatty acid chainsPolymer :lipid

• Used for…– Long term energy storage– Protection– Insulation– Waterproofing– Cell Membranes– Chemical Messengers

(steroids)

Long chains with lots of Carbon and Hydrogen (long chains), but little or no oxygen

Lipids in membranes

Are lipids important in a diet?

Lipids come in two flavors…Saturated: Single Bonds

• Animal Fats • Harder to digest• Solids at room temperature• Holds as many Hydrogen atoms as possible

Unsaturated: Double Bonds• Vegetable Oils • Easier to digest• Liquids at room Temperature• Does not hold as many hydrogen atoms as

possible

Lipids come in two flavors…Saturated: Single Bonds

• Animal Fats • Harder to digest• Solids at room temperature• Holds as many Hydrogen atoms as possible

Unsaturated: Double Bonds• Vegetable Oils • Easier to digest• Liquids at room Temperature• Does not hold as many hydrogen atoms as

possible

Your Turn! Make a quick hypothesis to why Unsaturated Fats are easier to break down (thus healthier for you) than Saturated Fats!It is easier for your body to break double bonds than single bonds due to the number of electrons. Aka, it’s easier to steal 1 electron from Carbon when it is sharing two versus just that one! (Like borrowing money!)

Common Misconceptions:Lipids – Good & Bad Cholesterol

Why are lipids so abundant in cheese?

What is a nucleic acid?

What is a nucleic acid?

DNA: Deoxyribonucleic Acid

DNA RNA Proteins!

How do nucleic acids relate to the

cheeseburger?

DNA Is transcribed into

RNA,which is then

translated into proteins.

Nucleic Acids

• Carbon, Hydrogen, Oxygen, Nitrogen, and two Phosphorus atoms arranged in 3 groups (monomers)

• Used for storing and transmitting cellular information in a code called DNA or RNA.

Nucleic Acids

• Monomers:

– Nitrogen Base• A, G, C, T or U

– 5-Carbon Simple Sugar• Deoxyribose (DNA) • Ribose (RNA)

– Phosphate group

• Polymer – Nucleotide

Your turn! What kind of macromolecules are

the Lady and the Tramp feasting on?

Organic molecules are the building blocks of life

They are broken down into monomers,

then rebuilt into polymers, then broken down again, then rebuilt

again! And so life goes on…

Your turn!

What kind of macromolecules did you/will you eat today?