Honors Bio Biochemistry Practice Quiz

How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long?

• 12

• 11

• 10

• 9

• 8

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?

• Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.

• Macromolecular synthesis occurs through the removal of water and digestion occurs through the addition of water.

• Dehydration reactions can occur only after hydrolysis.

• Hydrolysis creates monomers, and dehydration reactions break down polymers.

• A and B are correct.

A molecule with the formula C₁₈H₅₄O₂ is probably a

• carbohydrate

• fatty acid

• protein

• glycerol

• hydrocarbon

Which of the following statements is false for the class of biological molecules known as lipids?

• They are soluble in water.

• They are an important constituent of cell membranes.

• They contain more energy than proteins and carbohydrates.

• They are not true polymers.

• They contain hormones and cholesterol.

The bonding of two amino acid molecules to form a larger molecule requires which of the following?

• removal of a water molecule

• formation of an ionic bond

• addition of a water molecule

• formation of a hydrogen bond

• both A and C

Which term includes all others in the list?

• monosaccharide

• disaccharide

• starch

• carbohydrate

• polysaccharide

Sucrose is a disaccharide, composed of the monosaccharides glucose and fructose. The hydrolysis of sucrose by the enzyme sucrase results in

• bringing glucose and fructose together to form sucrose.

• the release of water from sucrose as the bond between glucose and fructose is broken.

• breaking the bond between glucose and fructose and forming new bonds from the atoms of water.

• production of water from the sugar as bonds are broken between the glucose monomers.

• utilization of water as a covalent bond is formed between glucose and fructose to form sucrase

Which of the following statements about enzymes is true?

• Enzymes increase the energy required for a chemical

  reaction.

• Enzymes increase the rate of a reaction.

• Enzymes change the direction of chemical reactions

• Enzymes are permanently altered by the reactions they catalyze.

• Enzymes prevent changes in substrate concentrations.

The active site of an enzyme is the region that

• maintains the induced fit in extreme pH environments

• is involved in the catalytic reaction of the enzyme.

• binds the products of the catalytic reaction by absorbing water

• adds water to the substrate during dehydration synthesis

• both c and d

Which curve represents the behavior of an enzyme taken from a bacterium that lives in hot springs at temperatures of 70°C or higher?

• curve 1

• curve 2

• curve 3

• curve 4

• curve 5