⭐️microbiology 130 chapter 5⭐️exam 2⭐️

Fill in the blanks to the following order ATP-->______+______+_____ And then used to resynthesize ____ ADP+_____+_____--->______

ATP->(ADP)+(phosphate g) +(energy) & then used to resynthesizes (ATP) ADP+(phosphate Group)+(Energy)->(ATP)

Enzyme inhibitors are classified as either _____ or _____ inhibitors

Enzyme inhibitors are classified as either (competitive) or (no competitive) inhibitors.

Define hydrolytic reactions

⭐ reactions which use water and in which chemical bonds are broken

Where does the energy to produce ATP come from?and how is it transferred

⭐Energy to produce ATP comes from catabolic metabolism of organic molecules (breakdown of food: carbohydrates, fat, proteins) ⭐️Energy from chemical bonds of food is transferred to ATP by excited electrons of hydrogen atoms from food ️

What is the functions of an enzyme ?

⭐act as a catalyst to speed up the reaction

Define reaction rate

⭐frequency of collision containing sufficient energy to bring about a reaction depends on the number of reactant molecules at or above the activation energy level.

Define competitive inhibitors

⭐they ️fill the active site of an enzyme and compete with the normal substrate for the active site!! ⭐️they can do this because it's shape / chemical structure is similar to those of the normal substrates. HOWEVER unlike substrates it does not undergo any reaction to firm products.

Explain the mechanism of enzymatic action.!!Know figure 5.4 on page 116!!

⭐️1. The substrate contacts the active site on the enzyme ⭐️2.the contact between the substrate and the active site form an enzyme-substrate complex ⭐3.️the substrate is then transformed into a produces ⭐️4.The products are released ⭐️the enzyme is recovered unchanged

What two classes of chemical reaction can metabolism be divided into

⭐️1. Those that require energy ⭐️2.those that release energy

What three principle stages make up the stages of respiration

⭐️1.first stage is glycolysis ⭐️2.second stage is the Krebs cycle ⭐️3.third stage is the electrons transport chain (system)

Hat two general processes are used to produce energy from glucose?

⭐️1.️cellular, respiration ⭐️2.fermentation

What three mechanisms of phosphorylation are used to generate ATP from ADP

⭐️1.️substrate-level phosphorylation ⭐️2.oxidative phosphorylation ⭐️3.Photophosphorylation

Anabolic processes often involve ____________, and they are ________

⭐️Anabolic processes often involve (dehydration synthesis reactions), and they are (endergonic).

Catabolic reactions are usually ______, and they are _______

⭐️Catabolic reactions are usually (hydrolytic reactions), and they are (exergonic).

Denaturation of protein involves the breakage of _______ _____ and other ________ bonds.

⭐️Denaturation of protein involves the breakage of (hydrogen) (bonds) and other (non-covalent) bonds.

Enzymes are biologically active _____

⭐️Enzymes are biologically active (proteins)

Enzymes are subject to various ️cellular control. Two primary types are the control of enzyme _____and the control of enzyme ______. (how much enzyme is ______ versus how ____it is.)

⭐️Enzymes are subject to various ️cellular control. Two primary types are the control of enzyme ( synthesis) and the control of enzyme (active) (how much enzyme is (present) versus how (active) it is.)

How do enzymes affect the activation energy of a reaction?

⭐️Enzymes speed up chemical reactions by lowering the activation energy. The activation energy is the amount of energy needed to start a reaction and if this is lowered the reaction can occur more rapidly. ⭐️DOES NOT PUT ENERGY INTO THE SYSTEM!

In living cells _____serve as catalysts.

⭐️In living cells (enzymes) serve as catalysts.

How does temperature affect enzyme activity?and how does the graph look like?

⭐️KNOW THE GRAPHS ON FIGURE 5.5!!!!( goes up at constant rate then, stays the same for very short time, then steeply goes down) ⭐️the enzymatic activity ( rate of reaction catalyzed by the enzyme) increases with increasing ️temperature until the enzyme, a protein, is denatured by heat and inactivated. At this point, the reaction rate falls steeply.

Metabolism Happens Through ______ Reactions.

⭐️Metabolism Happens Through (Redox) Reaction.

What happen in the electron transport chain (system)

⭐️NADH and FADH2, are oxidized, contributing the ️electrons they have carried from the substrates to a " cascade" of oxidation-reduction reactions involving a series of additional electron carriers. energy from these reaction is used to generate a considerable amount of ATP. ⭐️in respiration, most of the ATP is generated in the third step!

Name of enzymes usually end in ___

⭐️Name of enzymes usually end in (-ase)

On way to increase reaction rate is to ___________.

⭐️One way to increase reaction rate is to (increase the temperature). ⭐️by causing molecuales to move faster, heat increases both the frcuncy of collisions and the numbers of moleucus that attain activation energy.

The unique configuration of an enzyme enables it to "find" the correct _____ from among the large numbers of divers molecules in the cell

⭐️The unique configuration of an enzyme enables it to "find" the correct (substrate) from among the large numbers of divers molecules in the cell

Define NADP+

⭐️a coenzyme similar to NAD ⭐️NADP+ is primarily involved in anabolic (energy requiring) ️reactions.

Define CoA (coenezyme A

⭐️a coenzyme that function in decarboxylation ⭐️plays important role in breakdown of fats and in series of oxidizing ️reactions called the Krebs cycle.

Define enzymes

⭐️a molecule that catalyzed biochemical reactions in a living organism usually protein

What is a metabolic pathway?

⭐️a sequence of enzymatically catalyzed reactions occurring in the cell ⭐️ (sequences of chemical reactions) are determined by its enzymes, which are in turn determine rained by the ️cells genetic makeup.

Define enzyme-substrate complex, and what does it do?

⭐️a temporary union of an enzyme and its substrate. ⭐️enables the collision to be more effective and lowers the activation energy of the reactant.

Define catabolism, and do they release energy or require it?

⭐️all decomposition reactions in a living organism; the breakdown of complex organic compounds into simple one ⭐️in living cells, the enzyme -regulated chemical reactions that release energy are generally the once involved in catabolism ⭐️️An example is the when cells break down sugars into carbon dioxide and water.

Define anabolism, and are they energy requiring or energy releasing?

⭐️all synthesis reactions in a living organism; the building of complex organic molecules from simple once ⭐the enzyme-regulated ️energy-requiring reactions are mostly involved in anabolism!

Whats another name for a noncompetitive inhibitor

⭐️allosteric inhibitor

How does an oxidation-reduction happen?

⭐️an electron is transferred from molecule A to molecule B. In the process, molecule A is oxidized, and molecule B is reduced.

Define substrate

⭐️any compound with which an enzyme reacts

Why at a lower temperature some molecules don't have enough energy to cause a chemical reaction?

⭐️because molecules move slower at a lower temperature than at a higher temperature and so may not have enough energy to cause a chemica, reaction.

How to coenzymes assist the ️enzyme?

⭐️by accepting atoms removed from the substrate or by donating atoms required by the substrate.

Define denaturation

⭐️change in the molecular structure of a protein, usually making it nonfunctional. ⭐️loss of 3-D structure

Define endergonic

⭐️consumes more energy than they produce.

Define non-competitive inhibitors

⭐️do not compete with the substrate for the enzymes active site, instead, they interact with another part of the enzyme which is called allosteric site.

What does a oxidative phosphorylation do? And how does it generate ATP?

⭐️electrons are transferred from organic compounds to one group of electron carriers (usually to NAD+ and FAD). Then, the electrons are passed through a serious of different electron carriers to molecules of oxygen or other oxidized inorganic molecules. ⭐️the transfer of electrons from one electron carrier to the next releases energy, some which is used to generate ATP from ADP through a process called chemiosmois.

3.What is energy? What form of energy is utilized in the cell?

⭐️energy is the capacity to do work ⭐️There are two forms of energy 1.potential energy-stored 2.kinetic energy-energy of motion

Define ribozymes

⭐️enzyme consisting of RNA that specifically acts on strands of RNA to remove introns and splice together the remaining exons ⭐️ribozymes act as a catalyst, have active sites that bind to substrate, and are not used up in a chemical reaction

What's is a holoenzyme

⭐️enzyme consisting of an apoenzyme and a cofactor ⭐️whole active enzyme ⭐️if the cofactors removed then the apoenzyme won't function !

Define reduction

⭐️has gained one or more electrons.

Define a coenzyme

⭐️if the cofactor is an organic molecule it's called a coenzyme! ⭐️a nonprotein substance that is associated with and that activates and enzyme.

How does Photophosphorylation generate ATP?

⭐️in Photosynthesis, organism molecules are synthesized with the energy of light from the energy-poor building blocks carbon dioxide and water. ⭐️Photophosphorylationstarts this process by converting light energy to the chemical energy of ATP AND NADPH, which in turn are used to synthesize organic molecules.

What does substrate-level phosphorylation usually generate ATP?

⭐️in a substrate-level phosphorylation ATP is usually generated when a high energy phosphate group is directly transferred from a phsphorylated compound (a substrate) to ADP ⭐generally the phosphate group has already acquired its energy during an earlier reaction in which the substrate itself was oxidize.

Define feedback inhibition

⭐️inhibition of an enzyme in a particular pathway by the accumulation of the end-product of the pathway;also called end -product inhibition. ⭐️generally act on the first enzyme in a metabolic pathway. Because the enzyme is inhibited, the product of the first enzyme reaction in the pathway us no synthesized. Because that unsynthesized Product would normally be the substrate for the second enzyme in the pathway, the second reaction stops immediately as well. Thus entire pathway shuts down and so no new end-product is formed.

Define the Krebs cycle

⭐️is the oxidation of CoA (a derivative of pyruvic acid) to carbon dioxide, with production of some ATP, energy contain NADH, and another reduced electron carrier, FADH2

Define glycolysis

⭐️is the oxidation of glucose to pyruvic acid with the production of some ATP and energy-containing NADH.

Define dehydration

⭐️loss of hydrogen atoms from a substrate

What are the components of a holoenzyme?

⭐️many enzymes require both an apoenzyme (protein portion) and a cofactor (nonprotein portion) to become active. The apoenzyme and cofactor together make up the holoenzyme, or whole enzyme. The substrate is the reactant acted upon by the ️enzyme

Define the turn over number

⭐️maximum number of substrate molecuals an enzyme molecual converts to produce each second.

Define activation energy

⭐️minimum collision energy required for a chemical, reaction to occur.

How does pH affect enzyme activity?and how does the graph look like?

⭐️most enzymes have an optimum pH which their activity is characteristically maximal. ⭐️above or below this pH value, enzyme activity, and therefore the reaction rate decline. ⭐goes up rapidly, then it hits it's mad point, and rapidly goes down.

Define NAD+

⭐️nicotinamide adenine dinucleotide ⭐️a coenzyme that functions in the removal and transfer of hydrogen ion (H+) and electrons from substrate molecules ⭐️primerly involved in catabolic (energy yielding) reactions

Where does oxidative phosphorylation occur?

⭐️occurs in the plasma membrane of prokaryotes and in the inner mitochondria membrane of eukaryotes.

Where does Photophosphorylation occur?

⭐️only in photosynthetic cells, which contain light trapping pigments such as chlorophylls.

What is an oxidation-reduction

⭐️oxidation and reduction are always coupled, meaning that each time one ️substance is oxidized another is simostanley reduced. This is called oxidation-reduction, or a redox reaction.

Define exergonic

⭐️produce more energy than they are consumed.

Define dehydration synthesis reactions

⭐️reactions that release water

Define oxidation

⭐️removal of electrons from an atom or molecule, a reaction that often produces energy,

What is ADP?

⭐️stands for adenosine diphosphate ⭐️substance formed when ATP is hydrolyzed and energy is released

Define FAD

⭐️stands for flavin adenine dinucleotide ⭐️a coenzyme that functions in the removal and transfer of hydrogen ions (H+) and electrons from substrate molecules.

Define ATP(adenosine TriPhosphate)

⭐️stores energy derived from catabolic reactions and releases it later to drive anabolic reactions and preform other cellular work.

Define catalysts

⭐️substances that can speed up a chemical reaction (process of making /breaking bonds between atoms) without permanently altered themselves are called catalysts.

What are the factors that influence the activity of an enzyme.

⭐️temperature ⭐️pH ⭐️substrate concentration ⭐️presence or absence of inhibitors ⭐️enzyme concentration

What is a enzyme-substrate complex

⭐️temporary intermediate compound forms.

Define phosphorylation

⭐️the addition of a phosphate group to an organic molecule(chemical compound).

Define carbohydrate catabolism

⭐️the breakdown of carbohydrate molecules to produce energy. ⭐️an example is glucose

Define saturation

⭐️the condition of which the active site on an enzyme is occupied by the substrate or product at all time.

1.. What is the difference between an anabolic or a catabolic reaction? Which is exothermic? Endothermic?

⭐️the different between the two of them is that an anabolic reaction is building of complex organic molecules from simple once, while catabolic reactions are the break down of complex compounds into simpler once. ⭐️anabolic is endothermic endergonic, while catabolic is exothermic exergonic.

What is a cofactor

⭐️the nonprotein component of an enzyme.

Define collision theory

⭐️the principle that chemical reactions occur because energy is gained as particles collide ⭐️The collision theory states that all atoms, ions, and molecules are continuously moving and thus colliding with one another. ⭐️Atoms, ions and molecules must collide for reactions to occur.

What is apoenzyme

⭐️the protein portion of an enzyme which requires activation by a coenzyme

Define electron transport chain (system)

⭐️the sequence of electron carriers used in oxidative phosphorylation

What is an allosteric site?

⭐️the site on an enzyme at which a noncompetitive inhibitor binds. ⭐️this binding causes the active site to change its shape making it nonfunctional. Thus enzyme activity is reduced. (The effect can be reversible or irreversible)

Define metabolism

⭐️the sum of all the chemical reactions that occur in a living cell

what do the molecules of ATP consist of?

⭐️they consist of adenine, ribose, and three phosphate groups.

What factors determine nether a collision will cause a chemical reaction

⭐️velocity of colliding particles ⭐️their energy ⭐️their specific chemical configuration.

Explain the role of ATP in coupling anabolic and catabolic reactions

⭐️when complex molecules are split apart (catabolism), some of the energy is transferred to and trapped in ATP and the rest is given off as heat. When simple molecules are combined to form complex molecules (anabolic), ATP provides energy for synthesis, and again some energy is give off as heat.

How is ADP formed?

⭐️when the terminal phosphate group is spilt from ATP, adenosine diphosphate (ADP) is formed! And energy is released to drive anabolic ️️reactions.

How does substrate concentration affect enzyme activity?and how does the graph look like?

⭐️with increasing concentration of substrate molecules, the rate of reaction increases until the active sites on all the enzyme molecules are filled, at which point the maximum rate of reaction is reached.

What is usually the first stage in carbohydrate catabolism

⭐️️Glycolysis, the oxidation of glucose to pyruvic acid

️organisms release and store energy from organic molecules by a series of ______ ️️reactions rather than a ______ burst.

⭐️️organisms release and store energy from organic molecules by a series of (controlled) reactions rather than a (single) burst.

What happens when the +H concentration is changed drastically?

⭐️️when the +H concentration (pH) in the medium is changed drastically the proteins 3-D structure is altered( extreme change in pH can cause denaturation.!!)

️️Glycolysis means ____ of _____

⭐️️️Glycolysis means ____ of _____

What is Allosteric vs. competitive inhibition?

An allosteric inhibitor does not compete for the active site, instead in interacts with another part of the enzyme, while a competitive inhibitor competes for the active site with the substrate.