Intro to Bio (ch5-6) EXAM QUESTIONS

What is the biological risk of using salt on icy roads in parts of the country that have a cold winter season?

*The salt has the risk of leeching into the ground and creating a hypertonic environment for plant cells.* Plant root cells will grow in excess to try to reach fresh water. Plant cells will take on excess water from the melted ice and become turgid. Salt is in limited supply in the ecosystem and this type of overuse will make it even more so. The deer in these areas have the danger of consuming too much of it as they forage for food.

The second law of thermodynamics states that all energy transformations result in more disordered energy. How do living organisms, which depend on the conversion of potential energy to kinetic energy to fuel their activities, continue to live?

*They must constantly take in chemical potential energy for fuel and excrete waste.* Living things do not obey the laws of thermodynamics. They must constantly take in chemical potential energy for fuel. They excrete the disordered molecules and lose the disordered energy as heat. They take the disordered molecules and heat energy and use them to create new fuel.

Less energy is needed to bring about a reaction when an enzyme is present.

*True* False

Enzymes are named based on the substrate that they bind. This is possible because

enzymes all have the same shape. *an enzyme binds one specific substrate.* enzymes are used up in the reaction. an enzyme is only associated with one metabolic pathway. enzymes speed up the rate of a reaction.

Which of these words does not belong with the rest as it relates to concentration gradient?

osmosis diffusion passive transport *active transport* facilitated diffusion

Which of the following enables a cell to pick up and concentrate a specific type of molecule?

passive transport *receptor-mediated endocytosis* osmosis exocytosis facilitated diffusion

The changing of an enzyme's shape as the substrate binds to the active site is called the

substrate binding theory. *induced fit model.* metabolic pathway. energy of activation. enzyme binding theory.

When a cell is in a solution where the concentration of the solute is the same in the cell as in the solution, the solution is called

*isotonic.* hypertonic. hypotonic. osmotonic. Saturated

If blood cells are placed in a hypertonic solution, the cells will

*shrink due to water loss by the cell.* be unaffected since they have a cell membrane to separate them from the solution. swell due to diffusion. burst due to active transport. shrink due to the loss of solutes from the blood cell.

Which of the following is not an example of osmosis?

Salting meat serves as a preservative. Vegetables placed in fresh water firm up. *Sugar in coffee dissolves.* Strawberries placed in sugar become syrupy. Eating salty popcorn makes people's lips dry.

Which of the following is best associated with a coupled reaction?

a. ATP consumes energy from another metabolic reaction. b. ADP often transfers a phosphate to the reactant. *c. The metabolic reaction requires energy from ATP.* d. ATP gains a phosphate group. e. ADP is used up in the metabolic reaction.

Identify which of the following statements is not true.

a. ATP is formed when energy is released during cell respiration. b. When ATP becomes ADP + P, the amount of energy released is enough for a biological purpose. *c. ATP is comprised of a sugar, base, and two phosphate groups.* d. ATP contains the energy form used for cellular work. e. ADP is low in potential energy.

When a car burns gasoline, much of the energy is released in the form of heat. Which of the following best describes this process in relation to the first law of thermodynamics?

a. Energy is conserved. *b. Energy can be changed from one form to another.* c. Energy is often destroyed. d. All energy comes from the sun. e. Energy is always used up in reactions.

Simple diffusion of molecules occurs

a. from an area of lesser concentration to an area of greater concentration. *b. in nonliving systems as well as living systems.* c. across plasma membranes only through transport proteins. d. until those molecules are more highly concentrated on one side of the plasma membrane. e. only in molecules that are in a gaseous state.

What prevents a plant cell from bursting in a hypotonic solution?

a. plasma membrane b. transport proteins, which help pump the excess water out of the cell *c. the presence of a cell wall* d. water moving out of the cell e. the presence of chloroplasts

What process typically regulates the enzymes involved in metabolic reactions?

a. substrate inhibition b. entropy capture c. ATP blockage *d. feedback inhibition* e. temperature levels

Which of the following is not a type of potential energy?

the energy in a glucose molecule the energy contained in a rock sitting at the top of a cliff *the energy of a ball rolling down a hill* the energy contained in a hamburger the energy of a diver standing on a diving board