bio ch 5

which of the areas shown in the figure below indicates the presence of an enzyme in the movement of reactant over to product?

b

Pickles are often preserved in a 20-30% salt solution called brine. How does this method prevent contamination by microorganisms?

bacteria cant survive in hypertonic solution because they lose water

osmosis includes

both the diffusion of water and a semi-permeable membrane

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

cell wall

which of the following statements reflects what occurs in the flow of energy conversions through living systems?

chloroplasts convert solar energy to the chemical energy of nutrient molecules

the figure below demonstrates which key concept regarding cell activities?

couple reactions

which of the following terms best describes entropy?

disorder

why do metabolic pathways require tens to hundreds of different enzymes?

each enzyme has a specific substrate and produces a specific product

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

energy can be changed from one form to another

which of the following statements most accurately describes the first law of thermodynamics?

energy can be neither created nor destroyed but it can be changed from one form to another

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

in what function do the embedded membrane proteins at "c" serve?

facilitated and active transport

molecules move from greater to lesser concentration through a transport protein in

facilitated diffusion

What process typically regulates the enzymes involved in metabolic reactions?

feedback inhibition

the figure below reflects how these two cells would respond in a __ environment

hypertonic

a patient who is admitted to the hospital shares that she has been taking a series of "water pills" to help her lose weight. her skin and mucous membranes are dry, and she is complaining of a headache. the physician on call asks for an iv treatment to be promptly administered. based on the information given, what would likely be the type of iv solution given to this patient?

hypotonic

simple diffusion of molecules occurs

in nonliving systems as well as living systems

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 solute is the same in the cell as in the solution, the solution is called

isotonic

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?

muscular contraction

which of the following is a by product of photosynthesis that is used during cellular respiration?

oxygen

a white blood cell surrounds and engulfs a worn-out red blood cell, forming a vesicle around the red blood cell. this process is called

phagocytosis

the opposite of a turgid plant cell is a

plasmolyzed plant cell

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

receptor-mediated endocytosis

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 the set up shown in the figure below, which of the following statements would describe the conditions observed after 12 hours of time have elapsed?

the tube contents will be hypertonic to the beaker contents

When a potted house plant is wilting, the addition of water quickly changes the look of the plant. This can be accounted for by which of the following statements:

the water creates a hypotonic environment causing the cells to gain water

in feedback inhibition of a metabolic pathway, where does the inhibitor bind?

to the enzyme of the first reaction

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 of our kidneys reabsorb water to prevent it from all leaving through our urine.

which energy association is correct?

Kinetic energy is the energy of motion.

ATP releases energy when

a phosphate is removed

the part of the enzyme into which the substrate fits is called the

active site

the concentration of calcium in a cell is 3%. the concentration of calcium in the surrounding fluid is 1%. how could the cell obtain more calcium?

active transport

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

the figure below represents a metabolic pathway, what happens if enzyme2 is defective and nonfunctional?

substrate Y would not be metabolized

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

Once the substrate moves into the active site of the enzyme

the enzymes alters in shape to more closely fit the substrate

in the set up 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