Organic MoleculesMolecules of Life

Most “life” molecules have a backbone of carbon.

Carbon can form 4 bonds so many atoms can bond and branch off.

Many molecules are composed mostly of carbon & hydrogen = Hydrocarbons

Organic Molecules

Biomolecules may be made of hundreds to millions of atoms!

Large molecules are built from smaller, repeating units.

Monomer =

Polymer =

Building Blocks

Small molecular units that make up a polymer.

Long chains of monomers.

Monomer & Polymer

Classified into four main groups

CarbohydratesLipidsProteinsNucleic Acids

Life’s Large Polymers

-Made of: Monosaccharides These are simple sugars.

-When you put monosaccharides together, you get: Polysaccharide

CarbohydratesSTRUCTURE:

Starch – stored energy in plants

Glycogen – stored energy in animals

Cellulose – structural support in plants

Function of Carbohydrates:

- A key source of energy for the body.-They turn into energy for all cells.

Examples of Carbohydrates:

Monomers: Glycerol & Fatty Acids Polymers: Fat Energy Storage Hydrophobic:

◦ “Water Fearing”

Lipids: Fats

◦Saturated Fat – all fatty acid chains contain max of hydrogen atoms (all single bonds).

◦Solid at room temperature.

◦Contribute to an unhealthy diet.

Lipids: Saturated Fats

Unsaturated Fats – contain less than the maximum number of hydrogen atoms in the fatty acid chains.

Liquid at room temp.

Healthier choice.

Lipids: Unsaturated Fats

Carbon skeleton forms four fused rings. Chemical Message Example:

◦Testosterone (male hormone)◦Estrogen (female hormone)◦Cholesterol

Lipids: Steroids

Monomer: Amino Acid Polymer: Polypeptide

Examples & Uses: ◦Body Structures: Hair, Fur, Nails, Muscle.◦Long Term Nutrient Storage.◦Body Defense – Receptors on Cells ◦Control Chemical Reactions

Proteins

Watch enzyme animations: http://www.youtube.com/watch?v=XTUm-75

-PL4&feature=related

Let’s Watch!

Proteins: Enzymes Used to speed up chemical reactions in a cell.

(lowers the amount of energy needed)

End in “ase”◦ Protease breaks down proteins◦ Lipase breaks down fats

Enzymes are catalysts:◦ Speeds up reaction, can be used over and over

again. The reaction does not change it (like a key!)

Acts on a substrate: ◦ The substance that is changed during the reaction.

An enzyme lowers the energy needed so that the reaction can work at normal cell temperatures

Visualize that our classroom is now a cell, and you are either an enzyme (key) or a substance to be broken down called a substrate (lock).

Circulate to find which enzymes are specific to our substrates.

Quick Write: How does this activity help to represent the role of enzymes?

Role Play!

How an Enzyme Works: Shape of an enzyme only fits particular molecules (substrate)

Active site → where the substrate fits

How an Enzyme Works

Proteins are made of chains of amino acids twisted, folded and coiled into a unique shape.

Analogy: ◦ Yarn = string of amino acids◦ Sweater= protein with a purpose!

The “folds” determine the function. Denaturation: When proteins are affected and lose their shape.

Ex: Frying an Egg

Protein Shape

Cut the two different colors of paper into interlocking puzzle pieces.

Label one color ENZYME (Amylase) Label the other SUBSTRATE (Cracker) On the enzyme, label the point at which the

it locks into the substrate = ACTIVE SITE Cut out a small chunk of paper out of the

substrate where it touches the active site of the enzyme. Label the little piece = e-

At point of missing e-, cut the substrate in half.

Push the enzyme into the substrate to split the products!

Enzyme Model