Biothermodynamics

Question 1

Thermodynamics tells us about the transfer of ___ that can occur between __ ___.

Answer 1

energy, living organisms

Question 2

Energy associated with anything in motion; e.g. a flagella whipping back and forth

Answer 2

kinetic energy

Question 3

Found in objects that are not moving

Answer 3

potential energy

Question 4

Potential energy is like ___ energy. It allows the organism to make use of energy from processes like __ __ for use later. In biology potential energy is stored within the __ ___ of molecules such as ___ and ___ stored in the muscles that fuels the body activities

Answer 4

stored, food intake, chemical bonds, glucose, glycogen

Question 5

____ reactions are spontaneous, and there is a net ___ of free energy to the surroundings. This means the products are more ____ than the reactants. This means there is a ______ gibbs free energy

Answer 5

exergonic, release, stable, negative

Question 6

____ reactions are non spontaneous, and free energy is ___in from the surroundings. This means that the products are at a ___ energy than the reactants. This means there is a ____ gibbs free energy.

Answer 6

endergonic, absorbed, higher,positive

Question 7

Non spontaneous can be driven by linking them with ____ __ _____ reactions. For example, during the ___ of ___

Answer 7

energetically favorable spontaneous, breakdown, ATP

Question 8

ATP is a combination of an ____ base, ____ sugar, and ___ phosphate groups. ATP powers _____ chemical reactions through ____ and ____ energy from exergonic reactions. The bonds between the ___ groups store significant amounts of energy and release it when ____. This is because each phosphate group is ____ charged and close together, making the region ___. By breaking the bonds and releasing the molecules, a more ___ molecule results, and energy is ___. This makes its hydrolysis highly ____ because of how exergonic its breakdown is.

Answer 8

adenosine, ribose, 3, endergonic, harnessing, storing, phosphate, hydrolyzed, negatively, unstable, stable, release, favorable

Question 9

When ATP is hydrolyzed for energy, it becomes _____. ADP then must undergo ___ to reform ATP. This process is _____.

Answer 9

ADP, phosphorylation, endergonic

Question 10

ATP can capture and ___ energy from the exergonic reactions of ___ ____. That stored energy can then fuel _____ reactions.

Answer 10

store, oxidative phosphorylation, endergonic

Question 11

Cell ____ is all an organism’s chemical reaction. It makes the inaccessible __ ___ coming from food into available energy. It is categorized into ___ and ___ pathways, and provides the reactions necessary to produce the ____ every cell needs.

Answer 11

metabolism, stored molecules, catabolic, anabolic, energy

Question 12

pathways that breakdown complex molecules into simpler ones; tends to be energy releasing, and drives anabolic pathways

Answer 12

catabolic pathway

Question 13

pathways that use simple substrates to build a complex substrates; energy is consumed

Answer 13

anabolic pathway

Question 14

States that energy cannot be created or destroyed, only transferred and transformed

Answer 14

first law of thermodynamics

Question 15

States that the entropy of a closed system increases over time

Answer 15

second law of thermodynamics

Question 16

In general, as organisms grow and develop, they become more _____. However, they do so by making the ____ more disordered

Answer 16

ordered, disordered

Question 17

States that as a system approaches absolute zero temperature, entropy reaches a minimum

Answer 17

third law of thermodynamics

Question 18

Molecules that speed up reactions by lowering the activation energy without being consumed

Answer 18

catalysts

Question 19

Many reactions in the human body would take __ to be complete. Catalysts are the reason the reactions __ __ and keep up with our bodies. For a molecule to be changed to a product, it must overcome the __ ___, the energy required to break the starting molecule and reach an intermediate form. The ___ the activation energy the more quickly the reaction occurs

Answer 19

years, speed up, activation, lower

Question 20

Catalysts can stabilize the ____ ___, or provide an __ __ for the reaction. These both lower the activation energy

Answer 20

transition state, alternate pathway

Question 21

a biological macromolecule that serves as a catalyst to increase the rate of reactions; mostly proteins

Answer 21

enzymes

Question 22

The reactant or starting molecule that an enzyme acts on

Answer 22

substrate

Question 23

the location on an enzyme where a substrate binds

Answer 23

active site

Question 24

formed when enzymes and substrate are bound together by weak interactions

Answer 24

enzyme-substrate complex

Question 25

Enzymes are _____ to a substrate or a group of related substrates due to their ___, specifically the shape at their __ ____

Answer 25

specific, structures, active sites

Question 26

and old and outdated model of enzyme binding that says that the active site is exactly made to fit the substrate

Answer 26

lock and key model

Question 27

The new theory that says the structure of the enzyme molds to the substrate while maintaining specificity

Answer 27

induced fit model

Question 28

In the induced model, the molding of the enzyme provides a ____ fit of the substrate to the enzyme. This brings the __ __ of the substrate closer together and creates a more ___ environment for the reaction to occur

Answer 28

tighter, chemical groups, favorable

Question 29

Nonprotein molecules or ions required for an enzyme to function properly; can be permanently or reversibly bound during catalysis

Answer 29

cofactors

Question 30

Organic cofactors or ____, are composed of ___ and ___ groups. They can further be divided into ______ which bind reversibly to enzymes and __ groups which bind ___ to enzymes. Inorganic cofactors are composed of metal ions such as ____, or ____.

Answer 30

coenzymes, vitamins heme, cosubstrates, prosthetic, covalently, Fe, Mg

Question 31

First a substrate will bind to an ___ __ of an enzyme. it is held in place via ____ ______ bonds. While the substrate is bound to the active site, the enzymes catalyzes its conversion into a ___ molecule. Enzymes can convert many substrates into many products. Then the product molecule is ______ from the active site and a new substrate will bind

Answer 31

active site, temporary, noncovalent, product, released

Question 32

Enzymes are not ___ as part of a reaction, thus small amounts of enzymes can dramatically increase reaction rates through __. Enzymes also do not change the __ of a reaction or its ___ __ ___. They only accelerate what would already take place. Almost all enzymes are ___ meaning they are subject to being denatured and losing their function in ___ ___.

Answer 32

consumed, reuse, equilibrium, gibbs free energy, proteins, extreme conditions

Question 33

____ also known as proenzymes, are the __ ___ to enzymes. Once they are ___ they are turned into an active form that is able to function. For example, the enzyme ______ is usually inactive, but when the pH of the stomach becomes ____, such as when we are preparing to digest food, it is cleaved into the active form called _____, as its __ ___ is removed. It is then able to catalyze the digestion of proteins.

Answer 33

zymogens, inactive precursors, cleaved, pepsinogen, low, pepsin, blocking sequence

Question 34

RNA molecules that function as enzymes.

Answer 34

ribozymes

Question 35

Different ___ have different ideal pH’s for the enzymes associated with their function. For example, stomach enzymes like ___ function best at a __ pH. While intestinal enzymes like __ and ____ work best at a higher pH. The further you deviate from the ideal pH of the enzyme, the ___ the rate of the reaction as those enzymes start to ____

Answer 35

organs, pepsin, low, urease, trypsin, lower, denature

Question 36

As you increase ____ you generally see an increase in reaction rate. This is because the enzyme and substrate molecules have more __ __ and are bouncing around more quickly. This makes it easier for them to ____ with each other and to catalyze the reaction. If the temperature is raised too high, the enzyme will ____,

Answer 36

temperature, kinetic energy, collide, denature

Question 37

Enzymes in their ___ conditions can ___ into their __ ___, which results in a loss of function

Answer 37

non-optimal, denature, primary structure

Question 38

is critical to making sure only the reactions we need are occurring.

Answer 38

enzyme regulation

Question 39

At the genetic level, ___ that produce enzymes can either be __ or ___ depending on the needs of the cell.

Answer 39

genes, disabled activated

Question 40

At the physical level, enzymes can be stored in _____ to physically ____ it from reactions where we don’t need it. It can be _____ when the cell requires their activity

Answer 40

vesicles, isolate, released

Question 41

At the enzyme level, enzymes can be ___ from inactive to active forms. They can also be activated or disabled via ___ ____ (for example through _____). They can also be modified by having another molecule bind to them, altering their __ of activity.

Answer 41

cleaved, chemical modification, phosphorylation, level

Question 42

A form of regulation in which the end product inhibits the process that formed it as it accumulates

Answer 42

negative feedback/feedback inhibition

Question 43

A negative feedback system provides ___ ___ to stop too much product from being formed. This is the primary way the body maintains ____

Answer 43

automatic regulation, homeostasis

Question 44

When a product of an enzyme triggers even more of its own production

Answer 44

Positive feedback

Question 45

A positive feedback loop creates a loop that increases in ____. For example, in labor, the head of the fetus pushes against the ___, stimulating the brain to release ___. This molecule causes the ___ to contract, pushing the fetus further against the cervix, which stimulates the brain to release even more oxytocin

Answer 45

magnitude, cervix, oxytocin, uterus

Question 46

The maximum rate of a reaction

Answer 46

Vmax

Question 47

Half of the maximum rate of the reaction

Answer 47

1/2 Vmax

Question 48

The concentration of the substrate at 1/2Vmax

Answer 48

michaelis constant

Question 49

Vmax increases as the amount of ___ increases. However, too much substrate and no __ __, means substrate molecules will have to wait for enzymes to free up from their ____. This means the increase in reaction rate will taper off.

Answer 49

substrate, free enzymes, saturation

Question 50

Km is inversely proportional to the __ ___ of the enzyme to the substrate. If km is low, it means the enzyme binds to the substrate very ___. That means in order to reach 1/2Vmax, we do not need a lot of ___. When Km is high, it means that enzyme and substrate do not bind very easily, and in order to reach the 1/2Vmax, we need a higher ___ concentration. Km can only be changed with the use of __ ____. This is because Km is an ____ property

Answer 50

binding affinity, easily, substrate, substrate, certain inhibitors, intrinsic

Question 51

__ ___ is when a substance binds to the active site of the enzyme, preventing the substrate is bound. this is ____. They do not change ____, because by increasing the concentration of substrate, the presence of the competitive inhibitors can be ____, and the maximum rate of the reaction can be increased. However they increase the ___ by interfering with the binding of the substrate. They tend to be similar in ___ to the substrate

Answer 51

competitive inhibition, reversible, Vmax, overcome, Km, structure

Question 52

in _____ _____ the substance inhibits the action of an enzymes by binding to it at a location other than the active site. This lowers _____, because increasing the amount of substrate does not change the enzyme effectiveness. It also has no impact on ____, because it doesn’t effect the ability of the substrate to bind to the enzyme

Answer 52

non-competitive inhibition, Vmax, Km

Question 53

___ ____ occurs when a substance binds to the enzyme and induces the enzyme’s inactive form. __ ___ occurs when the substance binds and induces the enzyme’s active form. This happens at a site other than the __ ___. Allosteric inhibition can be ____, where binding results in an __ __ in the active site, or directly blocks the substrate binding, and it can also be______.

Answer 53

allosteric inhibition, allosteric activation, active site, competitive, induced changed, noncompetitive

Question 54

In ___ ___, one substrate attachment makes other substrates attach more easily to other active sites. The more substrate is present, the more _____ the enzyme can bind it.

Answer 54

positive cooperativity, effectively

Question 55

In __ ___, after the first substrate attaches, the enzyme alters to make additional attachment difficult

Answer 55

negative cooperativity

Question 56

Non enzyme proteins that bind to molecules can also show cooperativity, for example with ____ and ___.

Answer 56

hemoglobin, oxygen