Powers U1-U2 Most Missed

Saturated means to have ______ type of bonds

• single
• double
• triple
• quadruple

11. The human pancreas is an organ that plays an important role in the process of digestion. The pancreas secretes (releases) trypsin. Trypsin is an enzyme that breaks down proteins. Which statement BEST describes what occurs to the enzyme trypsin AFTER it digests (breaks down) a protein?

• The trypsin molecule is not chemically altered by the reaction and may be used again.
• After binding to a protein molecule, the trypsin molecule is destroyed and must be replaced.
• After binding to the protein molecule, trypsin is converted to a lipid and used for energy storage.

26. Insulin, hemoglobin and enzymes are examples of which macromolecule group?

• carbohydrates
• lipids
• nucleic acids
• proteins

30. Where is energy stored in a macromolecule?

• in the wall
• in the bonds between atoms
• in the electron cloud
• in the cell

Bonus: The enzymatic hydrolysis, or breakdown, of sucrose by the enzyme sucrase will result in the formation of its two monosaccharide components, glucose, and fructose, as seen in the model above. The activity of an enzyme is affected by many factors including temperature and pH. Each enzyme has an optimum temperature and pH at which its reaction rate is the fastest. The optimum pH range for sucrase activity is 4 - 8. Imagine the pH of the environment in which the hydrolysis of sucrose is to occur has dropped to 2. How will this drop in pH influence point D in the model?

• There will be no change to the components of point D with a drop in pH; only temperature can denature the enzyme.
• More of the substrate (A) will fit into the active site (C), so more products will be produced.
• The enzyme (B) will allow less of the substrate (A) to move into the active site (C).
• The substrate (A) will no longer fit into the active site (C) because the enzyme has changed shape.

The enzymatic hydrolysis, or breakdown, of sucrose by the enzyme sucrase will result in the formation of its two monosaccharide components, glucose and fructose, as seen in the model above. The activity of an enzyme is affected by many factors including temperature and pH. Each enzyme has an optimum temperature and pH at which its reaction rate is fastest. The optimum pH range for sucrase activity is 4 - 8. Imagine the pH of the environment in which the hydrolysis of sucrose is to occur has dropped to 2. How will this drop in pH influence point D in the model?

• There will be no change to the components of point D with a drop in pH; only temperature can denature the enzyme.
• More of the substrate (A) will fit into the active site (C), so more products will be produced.
• The enzyme (B) will allow less of the substrate (A) to move into the active site (C).
• The substrate (A) will no longer fit into the active site (C) because the enzyme has changed shape.

A person starts to eat a hamburger. As she takes a bite and chews, an enzyme called salivary lipase helps to begin the process of fat digestion. Which of these is the BEST description of the role of enzymes in digestion?

• Enzymes are acids that physically break down food molecules.
• Enzymes are cells that secrete saliva and other necessary substances needed for digestion.
• Enzymes are proteins that speed up the process of chemically breaking down food molecules.
• Enzymes moisten food to help teeth in the mechanical process of grinding and chewing.

The human pancreas is an organ that plays an important role in the process of digestion. The pancreas secretes an enzyme known as trypsin which helps to break down protein molecules. Which statement BEST describes what occurs to a molecule of the enzyme trypsin AFTER it binds to a molecule of protein?

• The trypsin molecule is not chemically altered by the reaction with protein and may be used again.
• After binding to a protein molecule, the trypsin molecule is destroyed and must be replaced.
• After binding to the protein molecule, trypsin is converted to a lipid and used for energy storage.
• The combined trypsin and protein molecule is utilized for energy to power cellular functions.

A well-tested explanation that explains a lot of observations is

• a hypothesis.
• an inference.
• a theory.
• a controlled experiment.

A map of eastern North America, showing the pH of rainfall in the various states, indicates that the pH of rain in New York State varies from 4.22 to 4.40. According to these figures, the most acidic rainfall in New York State has a pH of

• 4.22.
• 4.30.
• 4.35.
• 4.40.