C1.2 cell respiartion Flashcards
respiration
chemical reactions inside cells that release energy in form of ATP through oxidation of organic molecules (eg. glucose)
breathing
process of ventilation that causes inhale and exhale of air tho=rough muscular contractions of diaphragm and intercoastal muscle
has exchange
process of diffusion of gases between capillary and alveoli in the lungs
cell respiarton
controlled release of eneergy from organic compounds incells
usually from glucose or carbs
sometimes from lipids and fatty acids and proteins
aerobic respiration formula
C6H12O6 +6O2 -> 6CO2 +6H2O
glucose (organic compound) + oxygen
note- aerobic respiration gives better yield of ATP
explain involvement of ADP and ATP + respiration
ADP + Pi (inroganic phosphate) -> ATP
where respiartion creates the bond between the two Pi in the ADP and the last Pi added high eneergy bond producing ATP
when ATP is being formed, called ATP sythase= condensation, release water= reduction
when ADP and Pi are being produced= hydrolysis, intakes water= oxidation
what is ATP used for
energetic processes such as;
muscle contraction
active transport
protein synthesis
DNA/ RNA replication
vescile trasnport
call signaling
all rprocesses release heat eneergy and hence all energy eventually ends up as as heat, the heat energy intically can be used to raise the temp of the organism but eventually is lost to envionrment and cannot be used for metabollic processes
oxidtion
e- lost
o2 gain
h2 lost
reduction
e- gain
o2 lost
H2 gain
ADP +PI -> ATP
reduction
through phosphorylation addition of phosphate group
formation of ATP through phosphoralation happens in 3 ways:
phosphorolyation- occurs in chloroplast during photosynthesis
oxidative phosphorylation- occurs in the mitochondira during the e- transport chain (final step of respiratin)
substrate level phosphorylation - occurs in the mitochondira during krebs cycle (intermediate step of respiraiton
ATP is a sourced of instant energy in cell, explain
splitting of ATP into ADP releases energy in small and manageable bursts during times the cell is in need
while hydrolysis of ATP to ADP is single reaction, glucose breakdown recquires a long series of reactions therefore cells prefers ATP
ATP is mobile and transports chemical eneergy to where it is needed in the cell
where does cell respiartion take place
mitochondria
explain structures in mitochondria
circular DNA
outer membrane
matrix
inner membrane
inner membrane space
ribosmes (70S)
cristae
explain process of aerobic respiartion
glycolysis
link reaction
krebs cycle
electron transport chain
chemiosmosis
what is the general reaction in aerobic respiration
C6H12O6 +6O2 -> 6CO2 + 6H2O
In the arrow ->
ADP +Pi -> ATP
explain glycolysis
hexose sugar (6c) -> 2x pyruvate (2x 3c)
happens in cytoplasm
in this reaction; 2 ATP, 2 NADH (hydrogen acceptor) is produced
explain link reaction
happens twice per glucose molecule
pyruvate from glycolysis eneters mitochondrion matrix
pyruvate is oxidised
CoA= coenzyme: a carreir enters the reaction, and pyruvate us splitted (decarboxylation) as one co2 molecule is produced and Acetyl CoA is also produced (acetyl= 2c)
in the reaction, NAD is reduced into NADH
enzyme CoA removes 1 CO2 and hydrogen from pyruvate, removal of hydrogen- oxidation, removal of co2= decarboxylation
in general link reaction is known as oxidative decarboxylation
pyruvate + CoA -> Acetyl CoA + Co2
explain krebs cycle
happens twice per glucose molecule
1. Acetyl CoA enters reaction =, Coa returns to link reaction
2. Acetyl group (2c) joins a 4C sugar to form a 6c sugar
CoA is recycled back to link reaction
6c= citrate (citric acid)
3. oxidative decarboxylation occurs where NAD+ converts into NADPH (reduction)
co2 is removed from reaction
forms 5C
4. oxidative decarboxylation occurs again, NAD+ converts NADPH (reduction) one CO2 expelled from reaction
produces 4c
5. rearrangement
ADP-> ATP
substrates level phosphoralation, one ATP produced by substrate level phsophoralation per molecule of cycle
FAD->FADH2
NAD->NADPH
process is oxidative as NAD and FAD addition fo hydrogen
4c compound produced= oxolacetate
- acetyl added to 4c processes starts over
general yield of krebs cycle
2 atp
6 NADH
2 FADH2
steps involved in glycolysis
- phosphorylation
hexose sugar (6c) addition of 2 phosphates and 2 ATP are used = hexose phosphate
2.lysis (splitting), hexose phosphate is then split into 2 triose phosphate - oxidation
NAD+ -> NADH + H+ = reductionn
trio phosphate is oxidized (removal of hydrogen) to pyruvate NAD is reduced (addition of hydrogen to NADH+ Nad is the most common hydrogen acceptor - energy released from oxidation allows ATP formation, 4 ATP produced
ATP formed from ADP + Pi
by susbrate level phospholrylation 4ATP are produced
electron transport chain
series of transmembrane proteins in inner membrane of the mitochondria, acts as electron carriers
first step in etc
NADH dehydrogenase
this oxideses NADH into NAD+ (returns to matrix) and pumps H+ accross inner membrnae (matrix to inter membrane space) small area with high concentration of H+
second step etc
e- lost from NADH move along etc and activates next transmembrane protein=
succinate reductase
it oxidises FADH2-> FAD+ (returns to matrix) and pumps H+ accross inner membrane (matric-> inter membrane space
overall products of glycolysis
2 pyruavtes
2 ATP (as we used 2 ATP in beginning and produces 4 ATP net yield = 2ATP)
2 NADH
third step etc
2X e- lost frpm FADH2 move along etc activates
cytochrome oxidase
pumping of H+ in the inter membrane space forms an electrochemical graidnet that must be positive because= H+
this is maintained to allow chemiosmosis (diffusion of H+)
cytochrome oxidase reduces O2 (final electron acceptor) into H2O all free H+ in matrix are combined with O2 to keep the concentration of H+ high in the inter membrane space
last step etc
H+ from inter membrane space diffuse through ATP sythase by chemiosomosis movents of H+ drives rotation of ATP sythase and ATP is made
where does glycolysis occur in
cytoplasm
where does the link reaction take place
mitochndrial matrix
molecules in and out in glycolysis
in:
glucose x1
ATP x2
NAD x2
Pi x4
ADP x4
out
ATP x4
NADH x2
pyruvate x2
molecules in and out in link reacton
in:
CoA x2
pyruvate x2
NAD x2
out:
acytal CoA x2
CO2 x2
NADH x2
molecules in and out in krebs cycle
in;
Acetyl Coa x2
oxaloacetate x2
NAD x6
FAD x2
ADP x2
Pi x2
out;
CO2 x4
NADH x6
FADH2 x2
ATP x2
CoA x2
what happens when ATP is converted into ADP
energy released
hydrolysis reaction
which processes doesnt recquire ATP examples
catabolism
anaerobic respirartion bullet points
- doesnt occur in presecne of oxygen
- glycolysis occurs in cytoplasm glucose broken into 3c molecues= pyruavte
- 2ATP is released, said to be less efficient than aerobic respiration as less energy is released
- known as fermentation
lactic acid fermentation bullet points
- occurs in humans in certain activities eg. spritning
-lactate produced
-after performing vigurous excerise, get out of breath, not enough o2 can reach muscles, to produce ATP in fastest way to maximise power of muscle contraction anaerobic respiration takes place in muscle
-there is a max lactate conc tat body can tolerate as its toxic, causes cramps
-lactate must be broken down by liver into water and co2
-demand for o2 that builds up during period of anaerobic respiration= oxygen debt
alchol fermentation bullet points
-takes place bacter and some funghi eg. yeast and in plants when deprived of o2
-glucose-> 2 co2 + 2 ethanol + small amount of energy
-yeast used in baking, ethanol evaporates, co2 cant escape from dough, forms bubbles, dough rises and swells
-ethanol from fermentation used beer and wine, glucose from beer comes from batery and from wine from grapes
-most bioehtanol produced from sugar cane and maize, using yeast
-fermenters used to keep yeast in optimum conditions
alchol fermentation process
happens in yeast (funghi)
- glucose converts into pyruvate
- NAD + x2 -> NADH x2
- ADP +pi x2 -> 2ATP - pyruvate -> 2 acetaldehyde
co2 expelled
pyruvate decarboxylase (enzyme) - 2 acetaldehydhe -> 2 ethanol
alchol dehydrogenase (enzyme)
2x NADH (from first step) -> 2 x NAD+ ( goes back to first step)
lactate fermenatation steps
happens in humans
- glucose-> pyruvate
2x NAD+ -> 2 x NADH
2 x ADP +Pi -> 2xATP - pyruvate -> 2x lactate
2 x NADH ( from first step) -> 2 x NAD+ (goes back to first step)
uses lactate dehydrogenase (enzyme)
