MICRO230 Ch8

bonds; electrons

Energy management in a cell most often involves the making or breaking of chemical _____ and the transfer of _____ from one molecule to another.

2 ATP, 2 pyruvic acid, 2 NADH

For each glucose that enters glycolysis, the NET output is...

ATP, substrate, cofactor/coenzyme, water

Identify all the possible needs for an enzyme to work...

ATP, CO2, NADPH

Identify the direct components used to generate sugar in the Calvin cycle

oxidized, reduced

In a redox reaction, one compound is ____ and another compound is ______.

energy, water

Most condensation reactions require an input of _____ and result in a loss of _____

true

T/F: PS680 refers to photosystem II

false

T/F: in photosynthesis, the light-independent reactions provide the energy and reducing power needed for the light-dependent reactions

true (during photosynthesis, water is split)

T/F: light-dependent photosynthetic reactions are catabolic

true

T/F: metabolic pathways are interconnected

False

T/F: photosynthetic pigments harvest chemical energy and convert it to light energy

false (aquatic ecosystems)

T/F: plants are the principle producers of oxygen on earth

false (occurs in the light INDEPENDENT reactions)

T/F: the calvin cycle is part of the light-dependent reactions of photosynthesis

true

T/F: the souring of milk is primarily due to the activity of certain bacteria and is called homolactic fermentation

mitochondria, cell

The ETS is found embedded in the inner membrane of the _____ of eukaryotes while the ETS is found embedded in the _____ membrane of prokaryotes.

mitochondrion, cytoplasm

The Krebs cycle occurs in the __ of eukaryotic cells and the __ of bacteria.

lock and key

Which model is sometimes used to describe enzyme-substrate interactions?

Glycolysis

Which of the following metabolic pathways begins with glucose and yields 2 pyruvates?

1. Enzymes bind their substate but are not changed in the reaction 2. Enzymes lower the energy of activation for the reaction they catalyze 3. Enzymes are not consumed in the reaction they catalyze

Which of the following statements about enzymes are true?

nitrate, sulfate, carbonate, nitrate

Which oxidized compound can be used as a final electron acceptor in anaerobic respiration?

Enzymes

_____ act as catalysts in virtually all metabolic pathways

bacteria

_____ are a domain of life which contains anoxygenic organisms

carbohydrates (readily oxidized = give up electrons)

_____ are used as cellular energy sources because they are superior electron donors

Autotrophs

_____ can synthesize all macromolecules from carbon dioxide and minerals

Amphibolism

_____ describes a metabolism where the intermediate products of a catabolic reaction can be used in anabolic reactions

Amphibolism

_____ describes a metabolism where the intermediate products of a catabolic reactions can be used in anabolic reactions

competitive

_____ enzyme inhibition is a mechanism of regulation where the active site is blocked by a molecule that resembles the true substrate.

Chlorophyll

_____ is a pigment found in both PS680 and PS700

dentrification

_____ is an important process that is involved in the recycling of the nitrogen contained in organisms back into the biosphere

NAD

_____ is the most common redox (electron) carrier in cells

photolysis

_____ is the splitting of water using light energy during photosynthesis

Oxygen

_____ is the terminal electron acceptor in aerobic respiration

oxygen

_____ is the terminal electron acceptor in aerobic respiration

transamination

_____ reactions involve the transfer of an amino group an amino acid to a carbohydrate

simple, conjugated

a _____ enzyme consists of protein alone, while a _____ enzyme (or holoenzyme) consists of protein and nonprotein components

cofactor

a _____ is an organic or inorganic enzyme accessory molecule (must bind to apoenzyme in order for the enzyme to be fully functional. can be organic molecules like vitamins [coenzymes] or inorganic elements like metal ions copper and zinc)

endergonic (requires energy, anabolism) exergonic (releases energy, catabolism)

a chemical reaction that requires energy to proceed is referred to as a _____ reaction

coenzyme

a complex organic molecule, often derived from vitamins, that acts in conjunction with an enzyme is known as a....

Apoenzyme

a non-functional enzyme which needs a cofactor is called a:

photon

a quantum of light energy

Deamination

a(n) _____ reaction results in the removal of the amino group from an amino acid

Cytochromes

a(n) ______ is an iron containing (heme) protein electron carrier in the last phases of aerobic respiration

acetaldehyde

after the generation of pyruvate, pyruvate is converted into _____ which is typically reduced to form ethanol during alcohol fermentation

energy

all of life must use _____ in order to do work

constitutive enzymes

always present in relatively constant amounts regardless of the amount of substrate

catalyst

an enzyme acts as a biological _____ that alters the rate of a reaction without being changed by the reaction

ATP synthase

an enzyme in the mitochondrial cristae that harnesses the flux of hydrogen ions across the membrane during oxidative phosphorylation

Holoenzyme

apoenzyme + cofactor, conjugated enzyme

proton-motive force

as hydrogen ions accumulate between the inner and outer membranes of the mitochondrion, a _____ is generated which powers ATP production

slime layer, cell wall, capsule, nucleic acids, glycogen

carbohydrates are important in the structure of which cellular components?

accessory

carotenoids are _____ photosynthetic pigments that trap light and shuttle it to chlorophyll

ATP, NADPH

compared to oxygenic photosynthesis, anoxygenic photosynthestic pathways produce less ____ and may not produce _____

preventing the enzyme-substrate interaction, blocking the active site of the enzyme

competitive inhibition decreases the activity of an enzyme by...

labile

compounds are called _____ when they can be easily denatured, distorted, and/or degraded by mild changes to the environment

Catabolism

decomposition of complex compounds during cellular metabolism

oxygenic

during _____ photosynthesis, chlorophyll-containing organisms produce O2 as a waste product

loss of protein 3-D shape

during denaturation, which happens first to proteins?

propionic acid, ethanol, acetic acid, lactic acid

during fermentation, different organisms reduce pyruvate to a variety of chemical compounds including...

enzyme

each reaction in a metabolic pathway is catalyzed by a separate _____

protons and electrons

electron carriers shuttle both ____ and _____

protons and eletrons

electron carriers shuttle both _____ and _____

carbohydrates, lipids

energy-rich _____ (ie glucose) and _____ (ie fatty acids) can both enter respiration pathways

Induction

enzyme _____ is a type of control of enzyme synthesis where enzymes are made only when suitable substrates are present.

conjugated enzyme

enzyme with another molecule such as a metal or vitamin cofactor bonded covalently to it is called a:

site of action, type of action, substrate

enzymes are named based on.....

much larger

enzymes are typically ____ than substrates

weakly

enzymes bond ____ with their substrates

6

eventually, _____ carbon dioxide molecules will be produced from one molecule of glucose by the end of respiration

Acetyl CoA

feeds directly into the krebs cycle (Acetyl coenzyme A; the entry compound for the citric acid cycle in cellular respiration, formed from a fragment of pyruvate attached to a coenzyme.)

Bind to a cofactor

for an apoenzyme to become a functional holoenzyme, it must...

2 CO2 and 2 NADH

for each glucose that enters glycolysis, acetyl CoA formation results in the production of _____.

2

for each molecule of glucose that enters glycolysis, the last 5 reactions (of glycolysis) occur _____ times.

fructose (its isomer)

glucose-6-phosphate is converted into _____ -6-phosphate in the second reaction of glycolysis

9

glycolysis has _____ steps

anoxygenic

green and purple bacteria undergo photolithotropic or _____ photosynthesis

50 (6- carbon sugar yields 38)

how many ATPs can be synthesized from the oxidation of one 6-carbon fatty acid?

1

how many bonds must be broken in ADP to form AMP? (*think monophosphate)

2

how many net ATP are generated during fermentation?

6

how many oxygen molecules are consumed during electron transport for each glucose during aerobic respiration?

8 (citrate formation to oxaloacetate)

how many steps compose the Krebs cycle?

oxygen

Aerobic respiration requires _____, whereas fermentation and anaerobic respiration occur without this molecule

butanol, carbon dioxide, isopropanol, ethanol

Alcoholic fermentation in bacteria could result in the production of...

Metabolism

All of the chemical reactions that occur within a cell (catabolic + anabolic)

active

An enzyme's _____ site is unique for each substrate

Enzymes

Catalysts for chemical reactions in living things

alcoholic fermentation, acidic fermentation

identify 2 different fermentation pathways

water and CO2

identify what serves as energy-poor products of aerobic respiration

cell death

if internal cellular enzymes are denatured, it can lead to...

loss of proton motive force

if the membranes of the mitochondria were permeable to protons then what would happen?

substrate-level

in _____ _____ phosphorylation, phosphate groups are transferred from one molecule to AMP or ADP to form ATP

noncompetitive

in _____ enzyme inhibition, a regulatory molecule binds to a site other than the active site

competitive

in _____ inhibition, the regulator is often a product of the enzymatic reaction

Aerobic

in _____ respiration, electrons are transferred from fuel molecules to oxygen which acts as the terminal electron acceptor

Acetyl CoA

in aerobic respiration the first release of carbon dioxide occurs during the formation of ____ _____

oxygen

in anaerobic respiration, _____ is NOT used as a final electron acceptor

periplasmic

in bacteria, protons are moved from the cytoplasm to the _____ space during chemiosmosis

on the inner membrane of the mitochondria

in eukaryotes, ATP synthase enzymes are found...

mitochondrial

in eukaryotic cellular respiration, the change gradient that exists between the inner and outer _____ membranes during chemiosmosis is called proton motive force.

Glyceralhyde 3-Phosphate (G3P)

in glycolysis, _____ donates the electrons that reduce NAD to NADH

substrate (reactant)

in metabolic pathways, the products of one enzymatic reaction may act as the _____ for the next step in the pathway

acetic, lactic, succinic, formic acids, lower pH to 4.0

in mixed acid fermentation, pyruvic acid is converted into some combination of:

oxygen, water

in the last step of the ETS, the electrons are passed to _____ along with hydrogen which results in the formation of _____

aquatic ecosystems

in which ecosystem is more than 80% of the oxygen on earth produced by photosynthetic organisms?

enzyme repression

inhibits at the genetic level by controlling synthesis of key enzymes

Krebs cycle

intermediates of _____ can ultimately lead to purine and pyrimidine synthesis

Denaturation

loss of normal shape of a protein due to heat or other factor

cyclic

metabolic pathways in which the starting molecule is regenerated through the series of reactions are called _____ pathways

water

most condensation reactions involve the loss of:

aerobic

most heterotrophic organisms use _____ respiration to obtain energy

aerobic

most heterotropic organisms use _____ respiration to obtain energy

Glycolysis

multi-step, energy-yielding conversion of glucose to pyruvic acid

Adenine

nitrogen base found in DNA and RNA that component of ATP; pairs with thymine in DNA and with uracil in RNA

pece

often, regulation of metabolic pathways occurs with activation or repression of the ____ - maker enzyme.

pace

often, regulation of metabolic pathways occurs with activation or repression of the _____ - maker enzyme.

lose electrons

oxidation

Photophosphorylation

photosynthetic organisms use a sunlight-driven electron transport chain to generate ATP via _____

Denitrification

process by which bacteria convert nitrates into nitrogen gas

Specificity

protein folding determines the 3-D shape in enzymes needed for their _____ for a particular substrate (protein folding determines the 3-D shape in enzymes that is required for substrate specificity. during denaturation, the first thing proteins lose is their 3-D shape and active sites where substrates would bind)

ATP synthase

protons can only cross the mitochondrial inner membrane through _____ _____

Hydrolysis

reactions that involve the breaking of bonds and an input of water are called _____ reactions

Substrate

regulated enzyme activity is completely dependent on _____ concentration.

Endoenzymes

retained intracellularly and function there Most enzymes are endoenzymes

induced fit

slight changes occur in the shape of the enzyme in order to guide the substrate into the active site. this is referred to as an...

Anabolism

small --> large Constructive metabolism; the process of building up larger molecules from smaller ones through biosynthesis.

heterotrophs

some ____ can synthesize all cellular macromolecules from minerals and one organic carbon source

redox reaction

supply electrons to the electron transport system A chemical reaction involving the transfer of one or more electrons from one reactant to another

organic compounds

terminal electron acceptor in fermentation?

substrate level

the ATP generated in the Krebs cycle is produced by _____ phosphorylation

acetyl

the ____ group that starts the Krebs cycle can be used to synthesize lipids and proteins

carotenoids

the _____ are red, orange, and yellow pigments

regulatory site

the activity of an enzyme can be controlled through the binding of molecules to a site other than the active site is called a....

Phosphorylation

the addition of a phosphate group to a molecule

fixation

the addition of carbon dioxide to ribulose-1,5-biphosophate to begin the calvin cycle is known as carbon _____

hydrogen

the atom ___ is added to NAD to reduce it

dependent on the products from the light-dependent reactions to work

the calvin cycle is....

violet

the color of light closest to the 400 nm end of the visible light spectrum is _____

Hydrolysis

the digestion of larger substrates into smaller molecules, involving the use of water, is usually the result of ____ reactions

lactic acid

the end product of fermentation by human muscle cells is _____ _____

one

to form ADP, a total of _____ phosphate bond must be broken from ATP

lowers

typically, the presence of enzymes _____ the activation energy for a reaction to proceed

increased rate of glycolysis

what adaptation explains how some fermentative bacteria can grow as fast as they would in the presence of oxygen?

purines and pyrimidines

what can be anabolically produced with intermediates from the Krebs cycle?

oxygen

what is NOT a terminal electron acceptor in anaerobic respiration? oxygen, nitrate, carbonate, sulfate

promotes growth in oxygen rich areas of host benefits: 1 permits survival and growth in absence of oxygen 2 allows colonization of anaerobic environments 3 adapt to variations in availability of oxygen

what is NOT an advantage of fermentation to microbial survival and growth?

frees electrons, gives off O2

what is released upon photolysis (splitting water with light) during photosynthesis?

Krebs cycle

what is the "next step" for pyruvate at the end of glycolysis following normal aerobic or anaerobic respiration?

thylakoid membrane

what is the cellular location of photosynthetic pigments in eukaryotes?

phosphorylation of glucose (glucose added to phosphate)

what is the first step in glycolysis?

Vitamins

what is the most common component of coenzymes?

acetaldehyde

what is typically reduced to form ethanol during fermentation?

Apoenzyme

what term refers to a biological catalyst that lacks an essential cofactor?

anoxygenic

what type of photosynthesis does green and purple bacteria undergo?

oxygen, lactic

when ____ supplies have been depleted in human muscle cells, ATP can be produced by _____ acid fermentation for short periods of time

coenzyme

when combined with its apoenzyme, a _____ is an organic compound that functions to move (carry) functional groups from one substrate to another

binary fission

when the process of anabolism synthesizes sufficient macromolecules to support two cells and the chromosome has been duplicated, a bacterial cell will divide by a process called _____ _____

cyclic

when the starting molecule of a biochemical pathway is regenerated through the series of connected reactions, it is referred to as a(n) _____ pathway.

cell membranes

where are the photosynthetic regions in prokaryotic cells?

lipids and carbohydrates

which 2 macromolecules have the most accessible energy stored within their structures?

facilitate metabolic pathways

which best describes the function of enzymes?

beta oxidation

which catabolic pathway is used by fatty acids?

cyanide

which compound blocks cytochrome oxidase, causing a termination of aerobic respiration and death?

NADP

which compound is reduced via electrons from PS700?

catalase, peroxidase, superoxide dismutase

which enzymes neutralize toxic products of respiration in aerobic organisms?

light-dependent reactions

which generates ATP and NADPH? light dependent or light independent reactions?

ADP

which is NOT a common cellular coenzyme that carries electrons?

ADP (NAD+ is most common carrier then FAD)

which is NOT a common cellular coenzyme that carries electrons? NAD, ADP, FAD

annihilation

which is NOT a possible fate for a photon striking a photosynthetic pigment? absorbance, transmission, annihilation, reflection

oxygen

which is NOT associated with fermentation?

NOT: supplying energy for the reaction ARE: activation of the enzyme, orienting the enzyme and substrate

which is NOT function of metallic cofactors?

NADH is oxidized to NAD+

which occurs during fermentation?

1. NADH oxidized to NAD+

which occurs during fermentation? 1. NADH oxidized to NAD 2. NAD reduced to NADH 3. NADH reduced to NAD

coenzyme

which of the following acts as a carrier to move a chemical group from one substrate molecule to another? coenzyme, ATP, or metallic cofactor

high temperature, changes in pH, chemicals

which of the following can result in the denaturation of enzymes?

glucose will yield 2 pyruvates

which of the following identifies best the reason the Krebs cycle must occur twice per glucose molecule?

proteins

which of the following macromolecules can commonly act as a catalyst?

metal ions, coenzymes, small organic molecules

which of the following represent cofactors?

nitrate, sulfate, carbonate

which oxidized compounds can be used as a final electron acceptor in anaerobic respiration?

cytochrome a/a3 (cytochrome oxidase - receives electrons from cytochrome c, pick up hydrogen ions from solution, and react with oxygen to form molecule of water)

which part of the electron transport system catalyzes the terminal step of aerobic respiration?

presence of O2

which substance is a reminder that oxygenic photosynthesis is the dominant type of photosynthesis on the planet?

ribose (plus adenine and 3 phosphate groups)

which sugar is part of the structure of ATP?

Fermentation

which term describes the incomplete breakdown of glucose due to the absence of an electron acceptor for the electron transport system?

amination

which term is used to describe an addition of an amino group to a carbon skeleton?

Exoenzymes

which term is used to describe enzymes which work outside the cell?

oxidative phosphorylation

which term is used to describe the process of ATP production from the ETS? (The production of ATP using energy derived from the redox reactions of an electron transport chain; the third major stage of cellular respiration.)

heterolactic fermentation

which type of acidic fermentation produces mixed acid products?

700nm

which type of light do the pigments of PS700 use for photosynthesis?

glucose is split into 2 intermediate molecules so must occur twice

why do the last 5 reactions of glycolysis occur twice for each glucose substrate?

2 pyruvates released during glycolysis

why must the Krebs cycle occur twice per glucose molecule?

ATP

(acronym) is the useful final product of aerobic respiration

ATP

(adenosine triphosphate) main energy source that cells use for most of their work coupling energy release with energy requiring reactions

Chemiosmosis

A process for synthesizing ATP using the energy of an electrochemical gradient and the ATP synthase enzyme.

oxidation and reduction

A redox reaction involves the coupling of which 2 types of reactions?

noncompetitive

A(n) _____ inhibitor binds to a site on the enzyme that is not the active site

synthase

ATP _____ is an enzyme in the mitochondrial cristae that harnesses the flux of hydrogen ions across the membrane during oxidative phosphorylation

Calvin Cycle

ATP and NADPH are used to form high-energy intermediates in which cycle?

3

ATP has ____ phosphate groups.

photo

ATP is produced by the process of _____ - phosphorylation (prefix) in the light-dependent phase of photosynthesis

Adenosine Triphosphate (ATP)

ATP stands for...

38

At best, cells can generate _____ ATP from the complete oxidation of one glucose molecule during aerobic cellular respiration

Ubiquinone

Coenzyme Q is also known as

oxygen (NOT in fermentation!)

Consider the simplified aerobic respiration formula: sugar + O2 ---> ATP + CO2 + Heat (_____ is simply NOT part of the fermentation pathway)

ATP

Links anabolic reactions with catabolic reactions

lock and key

One type of enzyme fits one type of molecule. Change its shape and the enzyme will no longer work

wavelength (PS1 absorbs longer wavelengths above 680 nm VS PS2 absorbs shorter = 680 nm and below) (both are stationed in antennae [clusters of chlorophyll molecules in the thylakoid membranes] that absorb and send light to reaction centers)

PS700 and PS680 are named for the ____ of light to which they have the most sensitivity

photosystem 1 (PS680 = photosystem II)

PS700 refers to.....

Chemiosmosis

Production of ATP occurs by the process of _____, where hydrogen ions travel down their concentration gradient through channels in ATP synthase complexes.

Catabolism

Refers to the decomposition of complex compounds during cellular metabolism, usually with the release of energy (Metabolic pathways that break down molecules, releasing energy.)

active site

Region of an enzyme where the substrate binds (a region on an enzyme that binds to a protein or other substance during a reaction.)

inner mitochondrial, plasma

The electron transport chain is located in the __ membrane of eukaryotic cells and the __ membrane of bacteria.

Mitochondria, cytoplasm

The location of the Krebs cycle enzymes in eukaryotes is in the _____ matrix, while in prokaryotes the enzymes are found in the _____.

Substrate

The reactant on which an enzyme works.

Bioenergetics

The study of the mechanisms of cellular energy release, including catabolic and anabolic pathways, is called.... (the study of how energy flows through living organisms)

6 NADH, 2 FADH2, 4 CO2, 2 ATP

What are the products of the Krebs Cycle?

green

What color is reflected by chlorophyll?

increase substrate concentration, increase enzyme concentration, increase temperature (could be too hot), decrease temperature

What could INCREASE the rate of an enzymatic reaction which is currently not at optimal conditions?

ATP forms by substrate-level phosphorylation

What occurs in the last 3 steps of glycolysis?

green plants

Which are the primary photosynthesizers in terrestrial ecosystems?

citric acid

the first step of the Krebs cycle results in the formation of _____

phosphate

the high energy of ATP is located in the bonds of the _____ groups.

protons

the impermeability of the inner cristae membrane to ___ is crucial for the maintenance of the chemioosmotic gradient

fermentation

the incomplete breakdown of glucose in the absence of oxygen that yields only a small amount of ATP and produces a variety of byproducts is a process called...

sunlight sunlight --> CO2 & H2O = glucose (sugar for energy) photosynthesis anabolic process means product (sugar) contains more stored energy than substrates (CO2 & H2O) also, photosynthesis costs more ATP to make the sugar than ATP is produced from the catabolism of sugar in cellular respiration

the light-dependent reactions of photosynthesis are dependent on:

using or not using oxygen

the major difference between aerobic and anaerobic respiration is...

activation (activation energy: addition of an enzyme lowers reaction's activation energy which allows reaction to proceed at faster pace w/ reduced energy input)

the minimum amount of energy required for a reaction to proceed is termed the energy of _____

dependent

the phase of photosynthesis that is catabolic (energy releasing) is the light ____ reactions

dependent

the phase of photosynthesis that is catabolic (energy releasing) is the light _____ reactions

cell membranes

the photosymthetic pigments of photosynthesis are found in the _____ _____ of prokaryotes.

Glycolysis, krebs, respiratory

the primary catabolism of molecules by most organisms would include which of the 3 following pathways? respiratory chain, calvin cycle, krebs cycle, fermentation, glycolysis

heterolactic fermentation

the production of mixed acids, one being lactic acid, during fermentation is a good definition of ____ fermentation

Substrate

the specific molecule on which an enzyme acts

400 nm (violet) to 700 nm (red)

the spectrum of visible light is best described by the range between which two wavelengths?

Grana

the stacks of thylakoids embedded in the stroma of a chloroplast.

Gluconeogenesis (the formation of glucose from noncarbohydrate sources such as protein or fat...glycolysis in reverse: "making new sugar" or making glucose from pyruvate)

the synthesis of glucose from metabolic intermediates occurs through a process called _____

anoxygenic

the term _____ photosynthesis refers to photosynthesis in which bacteria use H2H4S1 or elemental sulfur rather than H2O as a source of electrons and therefore do not produce oxygen

repression (no longer being synthesized)

the term enzyme _____ refers to an inhibition of the genetic apparatus that synthesizes new copies of the enzyme which results in a decrease in the number of enzyme molecules.

primary

the term used to describe protein structure which consists of just the simple sequence of amino acids is called _____ structure

pyruvic acid

the three-carbon compound that is produced during glycolysis (needed for both the aerobic and anaerobic pathways of cellular respiration that follow glycolysis)

alcoholic and acidic

the two general categories of fermentation pathways are...

the sun

the ultimate source of most chemical energy in cells is from: