8 metabolism Flashcards
what is a metabolic pathway
any chain or cycle of linked reactions catlaysed by enzymes
types of enzyme inhibitor
competitive: binds to active site
non competitive: binds to enzyme
what is Vmax
maximum rate
in competitive inhibition what happens to Vmax that doesnt happen in non competitive inhibition
eventually the same as reaction without inhibitor.
which inhibitor is chemically similar to the substrate
competitive
which inhibitor doesnt bind to but changes shae of active site
competitive
what is allosteric inhibition
a form of non competitive inhibition
what is an allosteric site
a binding site on the surface of an enzyme other than the active site. In the end-product inhibition, the product of the last reaction of an enzyme binds to the allosteric site.
what happens when the inhibitor binds to an allosteric site in non competitive inhibition
it blocks the acitivity
what happens when a regulatory molecule binds to the allosteric site
the overall conformation of the enzyme changes
Which disease is caused by the parasite Plasmodium falciparum?
malaria
Which of the following is the correct explanation of how databases are used to identify potential new antimalarial drugs?
Databases with Plasmodium falciparum genome and protein sequence information were used to screen chemicals for possible interactions before starting lab research.
In most enzyme-catalysed reactions, you will measure any one of these:
The time taken for a particular substrate to be used up
The time taken for a specific product to be made
Amount (mass or volume) of substrate used up over a specific amount of time
Amount (mass or volume) of product made over a specific amount of time.
enzyme reactions formula
Rate (s -1 ) = 1/ t (where t is the time taken in seconds)
enzyme reactions graph
tempeartue along X AXIS (iv)
mean rate of decolourisation along Y AXIS (dv)
equation for cellular respiration
C6H12O6 + 6O2 –> 6CO2 + 6H2O + E (ATP+heat)
define cell respiration
the controlled release of energy from organic compounds in cells to form ATP
R where does glycolysis happen
cytoplasm
R where does the link reaction happen
mitochondrial matrix
R where does the krebs cycle happen
mitochondrial matrix
R where is the electron transport chain
inner membrane of mitochondria
R four stages of respiration
phosphorylation
R four stages of respiration
phosphorylation
lysis
oxidation
atp formation
R phosphorylation
cell uses ATP to phosphorylate hexose sugar (glucose) making hexose biphosphate
ATP adds a phosphate to intermediate compounds to make them unstable and likely to react
R lysis
hexose is split in half to make two triose sugars
R oxidation (in respiration)
each triose loses electrons and hydrogens
these are transferred to NAD+ to make NADH and H+
R ATP formation
ATP is produced by substrate level phosphorylation
2 pyravates are made
R net energy yield per glucose molecule
2 ATP plus 2 NADH + H+
(oxygen not required)
R how is each pyruvate converted into acetyl CoA (link reaction)
pyruvate is decarboxlated (CO2 released)
pyruvate is oxidized
- NAD+ gets reduced as follows:
NAD+ –> NADH + H+
NADH is an electron carrier
R what comes first link or krebs
link reaction then krebs cycle
R for each CoA that enters in the krebs cycle:
3 NAD+ reduced to 3 NADH
1 FAD reduced to FADH2
1 ATP molecule produced
R where is the ETC
inner mitochondrial membrane
R what does the ETC do
carry electrons from carrier molecules (NADH and FADH2) down to oxygen
- uses electron energy to pump H+ (protons) into the intermembrane space
- creates a proton gradient that allows for
R chemiosis
production of ATP when protons diffuse through ATP synthase back into the matriz
R waht is the process of making ATP called
oxidative phosphorylation (uses oxygen as final electron acceptor)
R what is the final electrona cceptor
oxygen gets reduced to H2O
helps maintain the hydrogen ion gradient
R ATP –>
ADP + Pi
R redox of NADH
NAD - oxidised
H - reduced
R what does NADP concern
photosynthesis
R reduction in respiration
makes 4 ATP
uses 2 ATP
so 2 NADH + H+
(electrons transferred from NAD+ to NADH + H+
R what provides the energy to atp synthase
the combination of the etc and the gradient of hydrogen ions. enables the mitochondria to produce ATP
R what does oxygen also do in the etc
As the last electron acceptor of the ETC, oxygen also helps in maintaining the hydrogen gradient in the matrix by binding with the free protons to form water. Oxygen accepts electrons and binds protons at the same time to form water.
R how many atp molecules does NADH give rise to
three
R how many atp molecules does FADH2 give rise to
two
R why does FADH2 generate fewer ATP molecules
it donates its electrons to the etc at a later step
R what does the inner mitochondrial membrane fold to give
cristae, and an increased surface area.
R reduced FAD and NAD+ temporarily store…
energy that is released during oxidation reactions of glycolysis, link reaction and krebs
R whats the last protein complex in the etc
cytochrome oxidase where the electrons are combined with oxygen and hydrogen to form water. as oxygen is the ultimate electron acceptor, this process is also called oxidatice phosphorylation.
R as the inner mitochondrial membrane is impermeable to protons,
this results in the development of a high concentration of H+ in the intermembrane space (higher than the matrix). the potential energy in the gradient is used by atp synthase to make atp. this process is also referred to a chemiosmosis because it involves the movement of ions (protons) across a membrane
P stages of photosynthesis
light dependent reaction
light independent reaction
P in which stage does non cyclic photophorylation happen
lds
P in what stage does cyclic phosphoryaltion happen
lis
P where does lds occur
thykloid membrane
P where does lis occur
stoma
P photosynthsis equation
2H20 –> 4H+ + O2 + 4e-
P electron carrier in photosynthesis
NADP
which method provides biochemical evidence that cells have begun to differentiate
observation with an electron microscope
where does decompoisition of breoth microbes not happen
in flasks that are boiled and then sealed or not sealed
