Remember the four atoms that are major components in all living things are: __________ These atoms in different combinations and shapes make up four Bio-Molecules 1. Proteins 2. Carbohydrates 3. Lipids 4. Nucleic Acids What do you remember about these four molecules?

Bio- molecules Bio-molecules are large (organic)molecules that make up living things. Life Two or more atoms bonded together Carbohydrates (sugars) Proteins Lipids (fats) Nucleic Acids

Functional groups -parts of organic molecules that are involved in chemical reactions They give organic molecules distinctive properties hydroxyl amino carbonyl (ketones and aldehydes) sulfhydryl carboxyl phosphate

Carbonyl C=O –O double bonded to C if C=O at end molecule = aldehyde if C=O in middle of molecule = ketone

Carboxyl –COOH –C double bonded to O & single bonded to OH group compounds with COOH = acids –fatty acids –amino acids

Amino -NH 2 –N attached to 2 H compounds with NH 2 = amines –amino acids NH 2 acts as base –ammonia picks up H + from solution

Sulfhydryl –SH –S bonded to H compounds with SH = thiols SH groups stabilize the structure of proteins

Phosphate –PO 4 –P bound to 4 O connects to C through an O lots of O = lots of negative charge –highly reactive transfers energy between organic molecules –ATP, GTP, etc.

Section 1.2 Summary – pages Suppose you wanted to learn how a certain fertilizer affects the growth of different varieties of plants. What is a controlled experiment? Your hypothesis states that the presence of this fertilizer will increase the growth rate of each plant variety.

Section 1.2 Summary – pages An experimental crop setup is designed to test the hypothesis. What is a controlled experiment? Fertilizer is present in the soil with the experimental plants, but not in the soil with the controls. All other conditions that are kept the same for both groups- soil, light, water- are constants

Section 1.2 Summary – pages The single thing in an experimental group that is different is the independent variable Think of the definition of “independent” Designing an experiment What is the independent variable in the plant experiment?

Section 1.2 Summary – pages During the experiment, the thing you are trying to measure is the dependent variable. Think of the definition of “dependent” The dependent variable occurs as a result of the independent variable Designing an experiment What is the dependent variable in the plant experiment? (What are we measuring as a result of the fertilizer)

PRE- LAB INFORMATION FOR: ENZYME ACTION LAB For this lab, we are going to focus on the bio-molecule: Protein….specifically, Enzymes A protein is a large, complex polymer composed of smaller subunits called amino acids.

Section 11.1 Summary – pages All actions, such as eating, running, and even thinking, depend on proteins called enzymes. So what? Why are proteins important???? You are composed of proteins- your skin, hair, eyes contain proteins….organs, muscles, bones… (everything that makes you…you.)

Section 11.1 Summary – pages Enzymes are proteins in your body that control the chemical reactions needed for life. (breaking stuff down and putting stuff together) Why is this important???

Without enzymes…. You wouldn’t be able to digest food for nutrients to make energy. Your body couldn’t make new cells to help you grow or replace dead cells. You wouldn’t be able to process information being passed through your neurons.

PRE- LAB INFORMATION FOR: ENZYME ACTION LAB There is an enzyme called Catalase found in MOST organisms. This enzyme has the ability to break down H 2 O 2 (which is Hydrogen Peroxide) Hydrogen Peroxide is toxic to most living organisms. H 2 O 2 is naturally produced in organisms as a by-product of cellular respiration (when your cells are making energy). Catalase quickly arrives on the scene to destroy the Hydrogen Peroxide before it can do too much damage.

Catalase speeds up the process of breaking down the Hydrogen Peroxide molecule into water and oxygen. 2 H 2 O 2 2 H 2 O + O 2 2 H 2 O 2 2 H 2 OO2O2

We can measure the rate of this chemical reaction by measuring the rate of the appearance of oxygen (O 2 ) We will be using CHICKEN LIVERS which naturally contains the enzyme protein CATALASE in its cells. You will need to choose an independent variable to use. So brainstorm things you think could possibly affect the rate of the chemical reaction Come up with a TESTABLE QUESTION… For instance: I wonder how the amount of chicken liver affects the rate of the chemical reaction. Hypothesis, the more chicken liver I use in a trial, the faster the hydrogen peroxide will break down into water and oxygen.