Chapter 5 Questions
When neurons release their neurotransmitters, they release them by secretory vesicles fusing with the plasma membrane thereby emptying their contents into an area that can stimulate some response. What type of cellular transport is occurring as the vesicle forms and then surfaces on the cell's plasma membrane?
exocytosis
Which of these words does not belong with the rest as it relates to concentration gradient?
active transport
Which is an example of potential energy rather than kinetic energy?
an apple made up of energy-rich macromolecules
Enzymes are named based on the substrate that they bind. This is possible because
an enzyme binds one specific substrate
Which one of the following molecules is able to move across the cell membrane by simple diffusion?
carbon dioxide
Probable factors that affect the passage of materials across cell membranes include all of the following except
color
Because it is a passive process, which membrane transport process can continue whether the cell is alive or dead?
diffusion
Which of the following terms best describes entropy?
disorder
Simple diffusion across a plasma membrane is called passive transport because it
does not require energy from the cell.
Molecules move from greater to lesser concentration through a transport protein in
facilitated diffusion
The figure below represents a metabolic pathway. What happens if Enzyme2 is defective and nonfunctional?
Substrate Y would not be metabolized.
Considering the ATP cycle, which of the following would have the most potential energy to perform work for cell activities?
ATP
Which of the following is an example of osmosis?
Cells in our kidneys reabsorb water to reduce the amount of water lost in our urine.
Which statement most accurately describes the second law of thermodynamics?
Energy cannot be changed from one form to another without a loss of usable energy.
Intestinal cells absorb glucose via active transport. What would happen if all the mitochondria within these intestinal cells were destroyed
Glucose absorption would decrease
Which energy association is correct?
Kinetic energy is energy of motion
The second law of thermodynamics states that all energy transformations result in more disordered energy. How can photosynthesis take more disordered carbon dioxide and water and convert them into glucose, which is more ordered?
Solar energy is being added to the reaction to create glucose
Both starch and cellulose are made by stringing together many glucose molecules, but starch is easily digested by humans, while cellulose is indigestible. The starch polysaccharide has every bond occurring below the sugar rings while the bonds in cellulose alternate between one bond above the ring and the next below the ring. How can you explain humans' inability to digest cellulose?
The enzyme that breaks down starch can only fit the specific bond configuration of bonds below the ring
In the setup shown in the figure below, which of the following statements would describe what would be observed after 12 hours of time have elapsed?
The level of the solution in the tube would rise because there are now more dissolved solutes in the tube than the beaker
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.
In feedback inhibition of a metabolic pathway, where does the inhibitor bind?
to the enzyme of the first reaction
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
Simple diffusion of molecules occurs
in nonliving systems as well as living systems
The changing of an enzyme's shape as the substrate binds to the active site is called the
induced fit model
Energy of activation
is the energy required for molecules to react with each other
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
ATP is a good source of energy for a cell because
its breakdown is coupled with energy-requiring reactions
Enzymes are able to speed up the rate of a reaction by
lowering the energy needed for the reaction to proceed
Which of the types of cellular activities listed below would not use ATP?
passive transport
The opposite of a turgid plant cell is a
plasmolyzed plant cell
Which of the following shows the flow of energy at the cellular level through the biosphere?
solar energy - chloroplast - mitochondria
The second law of thermodynamics states that all energy transformations result in more disordered energy. How does this relate to energy transformation in a living organism?
The energy taken in as food is eventually converted into heat energy.
The part of the enzyme into which the substrate fits is called the
active site
