Biology Quiz

The graph shows data obtained from an experiment in which a certain volume of a colorless substrate was converted over time by the enzyme alkaline phosphatase into a bright yellow product. Which option helps explain the rate of product formation over time?

• The substrate starts catalyzing the enzyme in the presence of the product.

• Active sites within the enzyme become inactive when products are formed.

• The time taken by the enzyme to make the product increases as the reaction progresses.

• A decrease in substrate concentration limits the amount of product formed by the enzyme.

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NGSS.HS-LS1-6

A researcher found soil bacteria that contain the enzyme lipase, which helps digest fats into fatty acids and glycerol. The researcher studied the effect of different temperatures on the activity of the bacterial enzyme lipase. The graph shows the data collected.

Based on the graph, what information could the researcher best conclude about the effect of temperature on lipase activity?

• Lipase shows maximum activity at 40°C.

• Lipase activity slowly increases above 50°C.

• Lipase denatures as temperatures exceed 25°C.

• Lipase activity remains constant between 30°C and 40°C.

Refer to the diagram showing enzyme activity at different pH levels. What will most likely happen when pepsin mixes with food in the stomach and moves to the small intestine, which has a pH of 6.0?

• Pepsin will change its pH range.

• Pepsin will become inactive.

• Pepsin will work with more efficiency at a higher pH.

• Pepsin will digest substances other than protein.

Which option correctly explains the property of carbon that allows the formation of these biomolecules?

• A. Carbon forms multiple bonds, all of which are ionic due to its atomic weight.

• B. Carbon is highly polar, which allows it to form bonds with different elements.

• C. Carbon has a small atomic size, which allows it to bond with multiple elements.

• D. Carbon is tetravalent, allowing it to form multiple covalent bonds with other atoms.

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NGSS.HS-LS1-6

Triglycerides, or saturated fatty acids, are essential components of cell plasma membranes. The structure of a triglyceride is shown. Which property allows the formation of triglycerides?

• Carbon can form biomolecules due to its large atomic radius.

• Carbon can form macromolecules because of its high atomic weight.

• Carbon can form polymers of biological origin due to its high density.

• Carbon can form long chains by forming covalent bonds with other carbon atoms.

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NGSS.HS-LS1-6

Carbon interacts with a diverse functional groups to form a wide variety of macromolecules. Which explains why carbon can form so many different macromolecules?

• Carbon possesses six protons.

• Carbon has a large atomic mass.

• Carbon has non-metallic properties.

• Carbon can form four covalent bonds.

Catenation is the binding of carbon atoms with other carbon atoms to form a chain or ring molecules. Examples of catenation in carbon are shown. How does this property help carbon form biomolecules?

• It allows carbon to change its form from one biomolecule to another easily.

• It allows carbon to form biomolecules that can exist in different forms within a cell.

• It allows carbon to rapidly bind with other carbon atoms to form a large biomolecule

• It allows carbon to form different biomolecules with the same number or carbon atoms

How does having four valence electrons make carbon an ideal element to form biological macromolecules?

• It allows carbon to form four covalent bonds.

• It allows carbon to exist in four different states.

• It allows carbon to form four different compounds.

• It allows carbon to have four different carbon-based structures.

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NGSS.HS-PS1-1

NGSS.HS-PS1-2

Two properties of carbon are given: 1. It can assemble into a variety of chain or ring structures. 2. It can form single, double, or triple bonds with other carbon atoms and other atoms. How do these properties contribute to carbon being considered an important element for living organisms?

• They allow carbon to form a variety of organic compounds that are the backbone of all biological molecules.

• They allow carbon to undergo chemical reactions faster, which ensures a constant supply of energy to living organisms.

• They allow carbon to bond with water molecules, which allows it to be easily transported within an organism’s body.

•   They allow carbon to have a flexible structure that can readily pass through different biological membranes.

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NGSS.HS-LS1-6

Cohesion is a property of water that makes water molecules attract each other. Adhesion is the property of water molecules to get attracted to other molecules. On the surface of the water, the cohesive force is greater than the adhesive force. This imbalance of forces makes the surface of water appear like a film. This phenomenon is called surface tension. Surface tension is a measure of how difficult it is to break the surface of a liquid. Which natural phenomenon is an example of surface tension?

• ice floating on water

• salts dissolving in water

• insects walking on water

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NGSS.HS-ESS2-5