1. Unit 2 Review

2. 1.What are the four essential elements to life? 2.What are the charges and locations of the three particles that make up an atom? 3.Are the atoms that compose a molecule covalently or ionicly bonded? 4.What is difference the relationship between elements and atoms?

3. 1.What are the four essential elements to life? Oxygen, carbon, hydrogen, and nitrogen. 2.What are the charges and locations of the three particles that make up an atom? The nucleus is composed of protons (+) and neutrons (no charge) and is surrounded by electrons (-). 3.Are the atoms that compose a molecule covalently or ionicly bonded? Covalently 4.What is the relationship between elements and atoms? Elements contain atoms.

4. 1.What atoms compose water? 2.Why is water considered a polar molecule? 3.What special property of water results in cohesion? 4.Why does ice float on top of liquid water?

5. 1.What atoms compose water? 2 H, 1 O 2.Why is water considered a polar molecule? The hydrogen end is slightly positive and the oxygen end is slightly negative. 3.What special property of water results in cohesion? Hydrogen bonding 4.Why does ice float on top of liquid water? It is less dense.

6. 1.The more acidic a solution, the higher amount of ____ ions. 2.Lye has far more ____ ions than stomach acid. 3.If something is neutral, its pH is _____ and has ____ number of ___ and ____ ions. 4.How does a buffer resist pH changes?

7. 1.The more acidic a solution, the higher amount of H + ions. 2.Lye has far more OH - ions than stomach acid. 3.If something is neutral, its pH is 7 and has equal number of H + and OH - ions. 4.How does a buffer resist pH changes? It removes H + when it is too acidic and adds H + ions when it is too basic.

8. 1.What are the two functions of carbohydrates? 2.What do you call carbohydrate’s monomer? 3.What is the elemental composition and ratio of carbohydrates? 4.Draw the general molecular shape of a carbohydrate.

9. 1.What are the two functions of carbohydrates? Energy storage and building blocks of support. 2.What do you call carbohydrate’s monomer? Monosaccharide 3.What is the elemental composition and ratio of carbohydrates? 1 C: 2 H: 1O 4.Draw the general molecular shape of a carbohydrate.

10. 1.What are the 3 groups of lipids? 2.Which lipid, along with proteins, make up the cell membrane? 3.What group of lipids does cholesterol belong to? 4.Draw the general molecular shape of a lipid.

11. 1.What are the 3 groups of lipids? Fats, phospholipids and steroids. 2.Which lipid, along with proteins, make up the cell membrane? Phospholipid 3.What group of lipids does cholesterol belong to? Steroid 4.Draw the general molecular shape of a lipid.

12. 1.What are the functions of proteins? 2.What element is unique to proteins compared to lipids and carbs? 3.What is the monomer of proteins? 4.What do we call biological catalysts?

13. 1.What are the functions of proteins? Structural makeup body such as muscle, skin, and hair, chemical messengers, and enzymes 2.What element is unique to proteins compared to lipids and carbs? N 3.What is the monomer of proteins? Amino acids 4.What do we call biological catalysts? Enzymes

14. 1.Do enzymes increase or decrease activation energy (barrier to starting a reaction)? 2.If catalase is an enzyme, what is its substrate? 3.What term refers to the changing shape of proteins due to temperature or pH? 4.What role do enzymes play in chemical reactions?

15. 1.Do enzymes increase or decrease activation energy (barrier to starting a reaction)? Decrease 2.If catalase is an enzyme, what is its substrate? Hydrogen peroxide 3.What term refers to the changing shape of proteins due to temperature or pH? Denaturation 4.What role do enzymes play in chemical reactions? Speed up reactions without becoming a reactant or product.

16. 1.What is a hypothesis? 2.Identify the experimental variable in this statement: If the pH of catalase is 10, then the reaction rate will be 5 because the chicken liver is no longer alive. 3.Identify the dependent variable in the above statement. 4.What is the purpose of the control set-up?

17. 1.What is a hypothesis? An educated guess or prediction of the outcome of the experiment. 2.Identify the experimental variable in this statement: If the pH of hydrogen peroxide is 10, then the reaction rate for the catalase will be 5 because the chicken liver is no longer alive. pH 3.Identify the dependent variable in the above statement. Reaction rate of the catalase 4.What is the purpose of the control set-up? So there is something to compare the experimental group to.