MCB 2610 Exam 3

are anaerobic respiration and fermentation the same thing?

no

can bacteria undergo both anaerobic respiration and fermentation?

yes

can eukarya undergo both anaerobic respiration and fermentation?

no

oxidative phosphorylation is used by organisms that use?

ETC and a chemical to generate ATP

how many molecules of ATP can be synthesized directly from oxidation of glucose to CO2

4

how many ATP do you get from both glycolysis and TCA cycle?

2

when is the most ATP made?

when NADH and FADH2 are oxidized in the ETC

how many electron carriers do we get from glycolysis?

2 NADH and 2H+

how many electron carriers do we get from pyruvate to acetyl CoA?

2 NADH and 2 H+

how many electron carriers do we get from TCA cycle

6 NADH and 6H+, 2 FADH2 and 2H+

the chemiosmotic model

membrane having a concentration gradient across the membrane by using a flow of electrons (proton gradient)

in the chemiosmotic model we build up a lot of?

potential energy to turn to kinetic energy

potential energy being turned into kinetic energy allows for?

ATP synthase to be turned on to make ATP

what generates a proton gradient

electrons passing through an electron transport system

what is the common electron carrier molecule?

NAD+

positive reduction potential means molecule is?

good at grabbing electrons

negative reduction potential means molecule is?

happy to give away elecrtons

reduction potential

tendency of molecule to acquire electrons

if you have an electron carrier at the very top (more negative) and an acceptor at the very bottom (more positive) will you generate a little bit of energy or a lot of energy?

a lot

why are carriers and acceptors that are close to each other not able to generate as much energy?

there is not as big of a difference in redox potential

everything in the membrane is organized by?

redox potential

in order to get electrons to flow off of a carrier onto a complex we have to have a carrier that has a more __ potential than the complex

negative

if we want the electron to flow again to another complex we have to have the next complex have a more __ redox potential that our other complex

positive

oxidation results in the __ of an electron

loss

reduction results in the __ of an electron

gain

electron transport chains pump protons across the?

membrane

why do we use the mitochondrial electron transport chain as a model ETC?

because it's highly conserved, very standardized and has 4 complexes that for the most part work the same way

why don't we used bacterial and archaeal ETC's as models?

there's more variability like more complexes

the mitochondrial electron transport chain is composed of a series of electron carriers that operate together to transfer electrons from?

NADH to FADH2 to a terminal acceptor O2

bigger proton gradient = ?

bigger potential energy and more ATP

why don't we just take electrons off of NADH and donate them directly to oxygen?

we wouldn't be able to pump as many protons therefore losing energy that we capture in the proton pumps

each carrier is reduced and then?

reoxidized

carriers are constantly recycled through ETC, why is this important?

because we have a limited amount of carriers

the difference in reduction potentials of electron carriers NADH and O2 is small or large?

large

in eukaryotes the ETC carriers are within the __ __ __ and connected by __ __ and __ __

inner mitochondrial membrane, coenzyme Q, cytochrome C

electron transfer is accompanied by proton movement across the?

inner mitochondrial membrane

bacterial and archaeal ETCs are located in the?

plasma membrane

many bacterial and archaeal ETCs are different than mitochondrial ETC how?

different electron carriers, 2 or 3 ETC complexes, some don't have coenzyme Q, may be branched or shorter

bacterial and archaeal ETCs - branced

where the carriers are going to donate into can change based on different environment

bacterial and archaeal ETCs - shorter

produce less ATP because they are not pumping as many protons/building up protein gradient

what drives the formation of ATP?

diffusion of protons back across membrane

ATP synthase is highly conserved in both?

structure and function; found in all 3 domains and functions like a rotary engine

ATP synthase

enzyme that uses PMF down gradient to catalyze ATP synthesis

where is ATP synthase found in eukaryotes/bacteria and archaea

eukarya - inner mitochondrial membrane, bacteria and archaea - inner plasma membrane

2 parts of rotary for ATP synthase

F0 and F1

where is F1 found vs. F0

F1 - ester side of membrane, F0 is embedded in plasma membrane

for every 3 protons one molecule of __ is produced

ATP

if no big gradient is present ATP synthase can work in reverse and?

hydrolyze ATP and spit out proteins

the rotary part of ATP synthase is found where?

c subunit

gamma subunit runs between?

F1 and F0 portion

top of gamma subunit is in?

c subunit

bottom of gamma subunit is in?

both alphas and beta subunit

when the c subunit spins, so does gamma, and every time the spindle moves through the alpha and beta subunits, it causes a?

conformational change of subunits

beta conformational changes allows for?

ADP and inorganic phosphate to bind and convert to ATP

alpha subunit forms the channel for which?

protons flow to generate energy and spin around c subunit

ATP yield in eukaryotic cells - glycolysis and TCA cycle

2 ATP via substrate level phosphorylation

ATP yield in eukaryotic cells - oxidative phosphorylation

28-34 ATP

ATP yield in eukaryotic cells - total yield per glucose?

~34 ATP

anaerobic respiration uses electron carriers other than?

oxygen

anaerobic respiration yields more or less energy?

less because electron acceptor is less positive than oxygen

is an ETC used in anaerobic respiration?

yes

terminal electron acceptor is not oxygen so you make a lot of ATP but is it as much as aerobic respiration?

no

can anaerobic respiration take place in oxygen or without it?

yes because we don't use it

do we still TCA and glycolysis in anaerobic respiration?

yes

chlorophyll a is found in?

eukarya and cyanobacteria

difference between chlorophyll a and b?

chlorophyll b has an ester group added

organisms that use chlorophyll undergo __ photophosphorylation

oxygenic

organisms that use bacteriochlorophyll undergo __ photophosphorylation

anoxygenic

difference between chlorophyll a and b vs. bacteriophyll

chlorophyll a and b wavelength of energy and absorb high energy light

why does chlorophyll a and b need a lot of energy?

to split water for electrons

bacteriochlorophyll is used in?

bacteria and archaea

do organism that used bacteriochlorophyll use water as an electron donor

no because wavelength of light they use doesn't have enough energy to pull e's off water

accessory pigments absorb at the same or different wavelengths than chlorophyll/bacteriochlorophyll

different

photosystems

I and II

do all bacteria use the same amount of photosystems

no some use both systems and some use one system

if bacteria use one photosystem which one do they use?

photosystem I

photosystems are composed of?

numerous antennae that absorb light energy

photosystems - light energy is passed to?

electron in reaction center

photosystems - electron is sent on to?

electron transport system

if you use both photosystems is the ETC going to be longer with more proton pumpers or shorter with less proton pumpers?

longer with more proton pumpers

anoxygenic - excites electrons off of something other than?

water

oxygenic - excites electrons off of?

water

phototrophic fueling processes - chlorophyll based phototrophy, we use __ to excite electrons and we do not use the __/__ pathway

light, TCA/glycolytic

oxygenic photophosphorylation is also known as

photosynthesis and oxygen as its end product

anoxygenic photosynthesis - who usually uses it?

anaerobic aquatic bacteria

anoxygenic photosynthesis - is water used as an electron source?

no so no oxygen is produced

anoxygenic photosynthesis - uses what kind of chlorophyll and mechanisms to generate reducing power?

bacteriochlorophylls

anoxygenic photosynthesis - carried out by?

phototrophic green bacteria, phototrophic purple bacteria and heliobacteria

oxygenic photosynthesis - carried out by?

photosynthetic eukaryotes and cyanobacteria

oxygenic photosynthesis - uses one or both photosystems?

both

oxygenic photosynthesis - oxygen is generated and released into?

the environment

oxygenic photosynthesis - most important pigments are?

chlorophylls a and b

oxygenic photosynthesis - short wavelength for water to?

knock electrons off of water

accessory pigments transfer?

light energy to chlorophylls

bacteriorhodopsin based phototrophy - who uses it?

some archaea

bacteriorhodopsin

membrane protein which functions as a light-driven proton pump

is an electron transport chain involved in bacteriorhodopsin based phototrophy

no

bacteriorhodopsin based phototrophy uses potential energy to

drive ATP synthase

bacteriorhodopsin based phototrophy -- proton pump is activated by?

light

anabolism - biosynthesis uses energy from?

catabolism