Chemistry of Life Review Worksheet | Part II | KEY. Directions: Answer the following ... Define enzyme: A type of protein (usually) that speeds up che...
Chemistry of Life Review Worksheet | Part II | KEY Directions: Answer the following questions the BEST you can without any help. After you have finished, notice what you don’t know and make note of this by highlighting the question. Now use notes, etc to finish. Proteins 1.
Fill in the table for proteins: Monomer
Polymer
Function
Amino Acid
Protein (Polypeptide)
Many different cellular functions/processes (ex: the protein hemoglobin transports oxygen)
2.
How many different amino acids are used to build proteins in organisms? 20 (our bodies can make 12 on their own, but we have to eat a variety of foods to be able to make the other 8 amino acids. 3. Fill in the blanks: The arrangement/order and length of amino acids determines the type of protein made. Even one incorrect amino acid placement can change a protein’s structure & function.
4.
What is the molecule pictured below? Amino Acid
5.
Label the molecule’s parts (a – c).
6.
Circle the group on the structure (pictured below) that is different for every one of these molecules. R-group or side chain
Amino group
Carboxyl group
7. What is another term for protein? Polypeptide 8.
What specific type of bonds form between amino acids? Peptide bonds, which are a type of covalent bond.
9. On the molecules pictured below, CIRCLE one complete amino acid and DRAW 2 arrows showing where the bonds between amino acids would form:
Enzymes and Chemical Reactions 10. Define enzyme: A type of protein (usually) that speeds up chemical reactions by lowering the activation energy. 11. What is another term for an enzyme? Catalyst 12. Why are enzymes important? a. They reduce the activation energy and speed up chemical reactions, allowing homeostasis to be maintained. b. Give two examples to support your answer in #12: i. Enzymes help break down food (metabolism/digestion) ii. Enzymes help build protein and other organic molecules iii. (you can have other answers as well) 13. What are the 3 MAIN characteristics of enzymes? Characteristics of Enzymes Specific Reusable Sensitive I know there were only 3 options, but you could also say CATALYST
Examples/Explanation Enzymes have a specific “active site” where only certain molecules can bond (that’s why it’s called a “lock and key model”). Their names are specific to what they do, ex: amylase breaks down amylose. Enzymes can be used over and over. Must stay within a set range of temperature, pH, ionic conditions otherwise their hydrogen bonds start to break apart. A type of protein (usually) that speeds up chemical reactions by lowering the activation energy.
14. What specifically causes enzymes to no longer work? Hydrogen bonds start to break apart and the enzyme/protein stops working because the conditions are too hot/cold, salty, or the pH is too high or low. 15. Match the following words with the proper definition: C Chemical Reactions D Reactants E Products B Equilibrium A Activation Energy
a. The amount of energy that is needed for a chemical reaction to start. b. When a reaction takes place at an equal rate in both directions. c. Change substances into different substances by breaking and forming bonds. d. The substances changed during a chemical reaction. e. The substances made by the chemical reaction.
16. The enzyme depicted in the graph (below), functions best at which temperature? About 40 degrees C, because this is where the reaction is at its peak – notice the dotted line drawn . 17. Describe what is happening in the following graph: The solid line represents a normal chemical reaction (with no enzyme), and the dotted line represents the same reaction with an enzyme being used. You can see the catalyzed reaction (one with the enzyme) requires less activation energy‐ so it’ll happen quicker. Uncatalyzed reactions require more activation energy as shown by the taller arrow.
18. Label the letters (a – c) on the pictures below. 19. Put the pictures of the chemical reaction in order by placing a 1, 2, or 3 in the box above the picture. 20. Describe what is happening in the boxes below the picture:
