Chapter 6 Sampling Homework

example of the chemical potential energy in ATP being turned into work

-a phosphate group is transferred from ATP to glucose during glycosis -after splitting ATP, a protein changes shape to pump ions across a membrane

how do organisms use energy according to the first law of thermodynamics

-animals eat to obtain chemical energy that they convert into kinetic energy -plants transform light energy into chemical energy by photosynthesis

feedback inhibition is important for the regulation of many metabolic pathways. which of the following are examples of feedback inhibition

-the production of isoleucine is halted by presence of excess isoleucine -the beginning of glycolysis is inhibited by high levels of ATP in the cell

what examples describe an energy transformation -a hot cup of coffee transfers heat to the air as it cools -an oven uses electrical energy to generate heat to bake a cake -a child runs and bumps into her brother, knocking him over -a plant uses solar energy to construct sugars in photosynthesis -an individual uses energy obtained from eating a hamburger to ride a bike

1,2,4

which of the following describe a catabolic pathway? -a pathway that transmits a signal within a cell -a pathway that consumes energy -a pathway that constructs molecules from smaller subunits -a pathway that breaks down molecules into smaller subunits

4

identify endergonic or exergonic -pedaling a bike up a steep hill -a ball rolling down a hill -metabolizing DNA into nucleotides -Constructing a protein from amino acids -generating carbohydrates in photosynthesis -breaking down glucose in cellular respiration

Endergonic: 1,4,5 exergonic: 2,3,6

how do enzymes recognize their substrates

a binding site that fits the shape and compliments the charge of the substrate

the second law of thermodynamics states that the entropy, or disorder, in a system constantly increases how do biological systems remain highly ordered

biological systems require an input of energy to remain highly ordered

identify whether the example describes an anabolic or catabolic pathway -a protein molecule is constructed from amino acid subunits -photosynthesis generates storage carbohydrates from CO2 and H2O -Glycosis converts one molecule of glucose to two molecules of pyruvate -a nucleic acid molecule is broken down into nucleotide subunits

catabolic: 1 and 2 anabolic: 3 and 4

what does the first law of thermodynamics state about energy

energy can be transformed but it cannot be either created or destroyed

both photosynthesis and cellular respiration are cellular processes that involve glucose, how d these two processes differently affect the metabolism of glucose?

glucose is produced during photosyntheses to hold the energy gathered from light, whereas glucose is broken down during cellular respiration to release stored cellular energy

activation energy is best described as the energy that

is required to bring the reactant molecules to a transition state

an enzyme catalyzes a reaction in a way that the results in a lower activation energy. what is the significance of a lower activation energy

it increases the rate of a cellular reaction

enzymes ____ the activation energy of a reaction

lower

When a muscle moves, a phosphate is removed from ATP. Breaking a bond in ATP allows the chemical energy stored in the bond to disperse in a muscle cell in the forms of mechanical energy and heat energy. How does the second law of thermodynamics apply to this process?

some energy does work and some energy escapes as thermal energy when the energy in ATP is released from the chemical bond

competitive inhibition

substance that resembles the normal substrate competes with the substrate for the active site

allosteric inhibition

the mechanism for inhibiting enzyme action in which a regulatory molecule binds to a second site (not the active site) and initiates a conformation change in the active site, preventing binding with the substrate

where is the chemical energy stored in ATP

the phosphate groups that repel each other due to multiple negatively charged atoms

why does the body use chemical energy?

the potential energy stored in chemical bonds can be released to perform work within a cell

what change occurs when an enzyme binds to a substrate with induced fit?

the shape of the enzyme's active site changes to better fit the substrate