Dehydration synthesis and hydrolysis Knowledge-Based Practice

Questions

1. 1.

   When a sample of cellulose undergoes complete hydrolysis into individual glucose monomers, how does the total mass of the resulting glucose compare to the initial dry mass of the cellulose?

   • A) It is less, because water molecules are eliminated during the breakdown of the polymer.
   • B) It is identical, because the individual glucose subunits are simply separated without adding new atoms.
   • C) It is less, because energy released from cleaved glycosidic bonds results in a loss of atomic mass.
   • D) It is greater, because water molecules are consumed and incorporated into the resulting glucose units.
2. 2.

   Which of the following statements correctly describes the chemical changes that occur during the assembly of a single triglyceride molecule from glycerol and three fatty acids via dehydration synthesis?

   • A) Three water molecules are consumed, forming three glycosidic linkages.
   • B) One water molecule is consumed, forming three peptide bonds.
   • C) One water molecule is released, forming three phosphodiester bonds.
   • D) Three water molecules are released, forming three ester bonds.
3. 3.

   A cell completely hydrolyzes a linear polypeptide chain composed of 20 amino acids into individual amino acids. How many water molecules are consumed in this reaction?

   • A) 10 water molecules
   • B) 20 water molecules
   • C) 21 water molecules
   • D) 19 water molecules
4. 4.

   During the formation of a covalent bond between two glucose monomers via dehydration synthesis, which event accurately describes how water is generated?

   • A) A water molecule is split so that a hydroxyl group and a hydrogen atom are added to the monomers.
   • B) A single monomer donates two hydrogen atoms and an oxygen atom to form the released water molecule.
   • C) One monomer donates a hydroxyl group and the other donates a hydrogen atom, releasing a water molecule.
   • D) An incoming water molecule donates electrons to create a covalent linkage before being consumed.
5. 5.

   Which of the following statements correctly compares dehydration synthesis and hydrolysis reactions in biological systems?

   • A) Hydrolysis links monomers into polymers by removing water molecules, whereas dehydration synthesis breaks down polymers into monomers.
   • B) Both dehydration synthesis and hydrolysis consume water molecules as reactants to form covalent bonds between monomers.
   • C) Dehydration synthesis breaks covalent bonds by adding water, whereas hydrolysis forms covalent bonds by releasing water molecules.
   • D) Dehydration synthesis forms covalent bonds between monomers with the release of a water molecule, whereas hydrolysis breaks covalent bonds within polymers through the addition of a water molecule.

Answers and step-by-step solutions appear after you finish the test.