Molecules of Life

What comes to mind when you hear or see the word organic?

 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 With a partner, determine what kind of bond you see in this illustration

 Biomolecules may be made of hundreds to millions of atoms!  Large molecules are built from smaller, repeating units. Monomer = Polymer = Small molecular units that make up a polymer. Long chains of monomers.

Carbohydrates Lipids Proteins Nucleic Acids

 What does the word “organic mean”?  List the four categories of organic molecules?

-Monomer: Monosaccharides These are simple sugars. - When you put monosaccharides together, you get: Polysaccharide STRUCTURE: Hydrogen, Oxygen and Carbon

 Starch – energy in plants  Glycogen – energy in animals  Cellulose – structural support in plants - A key source of energy for cells and the body. Examples of Carbohydrates :

 What is the function of a carbohydrate?  Give 2 food examples of carbohydrates.

What are the three structural examples of carbohydrates? Starch Glycogen Cellulose

Answer the questions on the starch lab and hand in before leaving class

-Monomers: Glycerol & Fatty Acids -Polymer: Fat They are hydrophobic – “water fearing” Structure Function: To Store Energy

◦ Saturated Fat – all fatty acid chains contain max of hydrogen atoms (all single bonds). ◦ Solid at room temperature. ◦ Contribute to an unhealthy diet.

 Unsaturated Fats – contain less than the maximum number of hydrogen atoms in the fatty acid chains.  Liquid at room temp.  Healthier choice.

 Example: ◦ Testosterone (male hormone) ◦ Estrogen (female hormone) ◦ Cholesterol

STRUCTURE  Made of Amino Acids Function Building blocks for parts of the body Examples ◦ Body Structures: Hair, Fur, Nails, Muscle. ◦ Long Term Nutrient Storage. ◦ Body Defense – Receptors on Cells ◦ Control Chemical Reactions

 Watch enzyme animations:  75-PL4&feature=related 75-PL4&feature=related

 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

How an Enzyme Works:  Shape of an enzyme only fits particular molecules (substrate)  Active site → where the substrate fits

 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!

1. What is being broken down? 2. Where the two parts meet? 3. What is doing the breaking? 4. What three things affect how well an enzymatic reactions occurs?

 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).  Quick Write: How does this activity help to represent the role of enzymes?  -What does the lock represent?  -What does the key represent?  -Where is the active site?  _What is the general steps that occur when a substrate is broken down by an enzyme?