2.5 Dehydration Synthesis and Hydrolysis Activity Name Date Block

Transcription

1 2.5 Dehydration Synthesis and Hydrolysis Activity Name Date Block Instructions: Complete the printout of this activity sheet with your lab partner. Show your work to your instructor when completed. Switch lab partners with another group to check your work. Make any additional changes to your work during our class discussion. Hand in your work. Points possible: 15 points Introduction: Use Chapter 2 section 2 in your Flexbook to define the following: 1. Enzyme -a protein that speeds up a chemical reaction by reducing the amount of activitation energy needed to start the reaction 2. Metabolism -the sum of all chemical reactions in an organism 3. Anabolism-reactions that build up bigger molecules form smaller ones (monomers become dimers and polymers) 4. Catabolism-reactions that break down molecules into smaller units and release energy (digestion) (polymer s and dimers become monomers) 5. What does the term synthesis mean? (Do a general dictionary search as needed.) to make or create 6. Note to keep in mind: Enzymes that break down substances (or digest them) are named using the name of the substance being broken down and adding the suffic ase. For instance, Lipase is the digestive enzyme that breaks down lipids. Enzymes that build larger dimers or polymers from monomers are named by taking the name of the large molecule that was built and adding the word synthase. So the enzyme that helps connect 3 Fatty acids and 1 glycerol together to create a lipid is called lipid synthase. 7. Study the reaction shown on page 42 (Figure 2.12) in your Flexbook. a. What is happening to sucrose in this reaction? Sucrose is being broken down in to Glucose and Fructose. Water is used b. What happens to water (color coded red) in this reaction? Water is broken into H and OH. OH completes the open bond on glucose and H completes the open bond on Fructose c. What is the name of the enzyme that makes this reaction occur? Sucrase

2 Part 1: Dehydration Synthesis and Hydrolysis Diagrams Reaction 1. Study the image showing glucose and fructose combining to form sucrose, or table sugar (a carbohydrate dimer). Use the terms monomer and dimer to define the terms dehydration synthesis and hydrolysis. a. Define Dehydration Synthesis: monomers are put together to make dimers (and polymers) b. Define Hydrolysis: polymers and dimers are broken apart into monomers c. Name the enzyme that would help this reaction occur: Hydrolysis: sucrase. Dehydration synthesis: sucrose synthase Reaction 2: Observe the reaction showing amino acids reacting to form a polypeptide. Note: peptides and proteins are the same thing. (An amino acid dimer is also called a dipeptide. It is also a small protein.) a. Write a word equation to describe what is happening in this diagram: 4 amino acids 1 polypeptide or protein + 3 water molecules b. Write the name of the enzyme that helps this reaction occur: protein synthase or polypeptide synthase Reaction 3. Observe the reaction showing glucose molecules reacting to form maltose, a carbohydrate dimer. a. Write a word equation to describe what is happening in this diagram: glucose + glucose maltose + water b. Write the name of the enzyme that helps this reaction happen: maltose synthase

3 Reaction 4. Study the image below showing glucose and fructose combining to form sucrose, or table sugar (a carbohydrate dimer). a. Write a word equation to describe Sucrose synthase what is happening in this diagram: Glucose + Fructose Sucrose + water b. Write the name of the enzyme that helps this reaction happen: sucrose synthase Part 2: Completing Dehydration and hydrolysis reactions Use the following example to complete the dehydration synthesis of the given reactants for reactions A, B, and C. Use the example provided to draw all products formed. Example: Reaction A

4 Reaction B Reaction C Reaction D. The reaction below shows the hydrolysis of a dipeptide to form two smaller monomers, alanine and glycine. Using what you know about dehydration and hydrolysis, finish the drawing of the reaction below:

5 Analysis Questions 1. As growth occurs in the body, new substances must by synthesized. For example, muscles get larger, and amino acids that are eaten must be converted into muscle proteins such as actin and myosin. Which of the chemical processes described in this assignment causes monomers to be joined together to form polymers like proteins? Dehydration synthesis 2. What type of chemical reaction is involved in the breakdown of polymers consumed during a meal into smaller monomers? Digestion or hydrolysis 3. Describe how water is created during the process of dehydration synthesis. An H atom from one monomer and an OH pair of atoms from another monomer are removed to form water. The open unpaired electrons left on the monomers are now paired to form a new bond that joins the two monomers to form the dimer (or polymer). 4. Explain the difference between sucrase and sucrose synthase. Sucrase is the digestive enzyme that breaks down sucrose into glucose and fructose monomers. Sucrose synthase is the dehydration synthesis enzyme that joins glucose and fructose to make sucrose. Only plants have this enzyme and can do this reaction after photosynthesis occurs. 5. Define the terms peptide and dipeptide. A peptide is a polymer made up of three or more amino acids. A dipeptide is a dimer made up of two amino acids. 5. Use the following terms in a sentence: dehydration synthesis, hydrolysis, anabolism, catabolism, and digestion : Dehydration synthesis is the building of dimers and polymers from monomers, this is also called anabolism. Catabolism and digestion are both the breakdown of polymers and dimers into monomers. All of these reactions together are called metabolism. 6. Fill in the blanks. Above the arrow write the name of the enzyme needed to make the reaction happen. a. + maltose + b. dipeptide + amino acid + amino acid c. glucose + fructose + d. 3 Fatty Acids + 1 lipid +