MCB 2610: Exam 3 pt. 10

where does glycolysis occur in eukaryotes and prokaryotes?

cytoplasm

where does the TCA occur in eukaryotes and prokaryotes?

eukaryotes - mitochondria, prokaryotes - cytoplasm

where does the ETC occur in eukaryotes and prokaryotes?

eukaryotes - inner mitochondrial membrane, prokaryotes - plasma membrane

why is fermentation used? (2 reasons)

some microorganisms don't have an ETC and some encode genes for ETC but something is going on in the environment blocking them from using ETC

do we use the ETC in fermentation?

no and we don't generate a lot of ATP because we are using substrate level phosphorylation

do we go through the TCA cycle in fermentation

no only glycolysis

fermentation allows organisms to?

adjust to changes in their environment

what is used as an endogenous (within the cell) electron acceptor (organic molecule gets reduced)

pyruvate or derivative

is the substrate fully oxidized?

no

is oxygen needed in Fermentation?

no

does oxidative phosphorylation occur in f

no, ATP is formed by substrate-level phosphorylation giving less energy

aerobic respiration uses what as its final electron acceptor?

oxygen

anaerobic respiration uses what as its final electron acceptor?

exogenous acceptor (nitrate, sulfate, etc.)

fermentation uses what as its final electron acceptor?

endogenous electron acceptor (pyruvate - no ETC)

in fermentation how do we get ATP?

PO4 is transferred to ADP from a high energy molecule (PEP)

fermentation - types

lactic acid, alcoholic and mixed acid fermentation

lactic acid fermentation is carried out by?

gram-positive microbes (LAB, can also be gram-negatives)

LAB ferment sugar to?

lactic acid

LAB includes?

gram negative and positives, pathogens, normal flora, microbes used to make yogurt, etc.

2 types of lactic acid fermentation

homolactic and heterolactic

homolactic yields how many products?

1 - lactic acid

heterolactic yields how many products?

2 - lactic acid and ethanol

heterolactic fermentation uses what kind of glycolysis?

pentose phosphate

homolactic fermentation makes a net of how many ATP?

2

heterolactic fermentation makes a net of how many ATP?

1

in alcoholic fermentation we go through glycolysis via?

embden meyerhof

alcoholic fermentation is carried out by?

yeast and some bacteria

alcoholic fermentation produces largely?

ethanol and CO2

mixed acid fermentation

several bacteria and fungi produce a mixture of fermentation products

why do we get so many different products in mixed acid fermentation?

we can take multiple pathways to regulate electrons

mixed acid fermentation is an important?

commercial pathway

how do microbes get nutrition from compounds other than glucose?

polysaccharides, proteins and amino acids and lipids

polysaccharides are?

partially broken down into smaller subunits by secreted enzymes outside of cell

when polysaccharides are partially broken down into smaller subunits by secreted enzymes outside of cell, the smaller subunits can begin to be?

broken down by the usual pathways

proteis and amino acids - proteases break polypeptides into?

individual amino acids

individual amino acids have the amino group detached, leaving?

organic acid that can be used in TCA cycle

lipids - lipases will separate fatty acids from?

glycerol in phospholipids/triglycerides

if you can catabolize fats do you generate a lot or a little bit of energy?

a lot

lipids - the beta oxidation pathway cleaves fatty acids into small carbon chunks that can be?

sent into TCA cycle individually for processing

lipid pathway is very tightly regulated in order to prevent?

cell from breaking down its own lipids for energy purposes

why is it problematic if cell breaks down its own lipids for energy purposes?

lipids are found in plasma membrane

why do we get so much energy from breaking down lipids?

because we keep breaking carbons down and funnel them through TCA cycle generating more electron carriers, higher proton gradient = more ATP

where is the cleavage site?

between carbons 2 and 3

chemolithotrophy is carried out by?

chemolithotrophs

chemolithotrophy - electrons are released from energy source which is?

inorganic molecule

chemolithotrophy - do we go through glycolysis/TCA cycle?

no

chemolithotrophy - electron from energy source is transferred to terminal electron acceptor by __, what is the terminal electron acceptor

ETC, oxygen

chemolithotrophy - ATP is synthesized by?

oxidative phosphorylation

chemolithotrophy - do we produced a lot of energy as compared to aerobic vs. anaerobic?

no because reduction potential of inorganic molecules is much more positive

do we go through glucose more rapidly in aerobic, fermentation, anaerobic, etc.

fermentation

why do we go through glucose more rapidly in fermentation?

because we don't generate as much ATP so we need glucose to make it

chemolithotrophic fueling process - what do you need to make ATP

carbon source

photophosphorylation

ATP synthesis using light to create an electron gradient

is photophosphorylation the same as photosynthesis?

no

photosynthesis combines what?

phototrophy and carbon fixation to produce carbon compounds

light reactions capture energy and use it to?

create a proton motive force to synthesize ATP

in eukarya, the site of light capture is the?

photosystem in thylakoid structures

thylakoid structures do what?

pump protons across

who undergoes photophosphorylation?

gram-negative because they have thylakoid like structures where we find ETC components

we need light for energy and have to harvest light so we need?

photo pigments