run for your life Flashcards
is ATP water soluble
yes
has polar groups
what type of reaction forms ADP and Pi from ATP
hydrolysis
what type of reaction forms ATP from ADP and Pi
phosphorylation
what is respiration
process of breaking down a respiratory substrate in order to produce ATP using oxygen
examples of a respiratory substrate
glucose
fatty acids
amino acids
what is the energy formed from respiration used for
to phosphorylate ADP to form ATP
what are the stages of aerobic respiration
- glycolysis
- the Link reaction
- the Krebs cycle
- oxidative phosphorylation
what are NAD and FAD
coenzymes
responsible for transferring H between molecules
can reduce/ oxidise molecules
what is coenzyme A
responsible for transfer of acetate
mitochondria outer membrane
smooth
permeable to several small molecules
mitochondria inner membrane
folded (into cristae)
less permeable
site of electron transport chain used in oxidative phosphorylation
location of ATP synthase enzymes
mitochondria inter membrane space
low pH cos go high conc of protons
conc grad formed during oxidative phosphorylation
which is essential for ATP synthesis
mitochondria matrix
aqueous sol within inner membrane
contains ribosomes, enzymes, circular mitochondrial DNA
where does glycolysis occur
cytoplasm
where does the Link reaction occur
matrix of mitochondria
where does the Krebs cycle occur
matrix of mitochondria
where does oxidative phosphorylation occur
inner membrane of mitochondria
does glycolysis require oxygen
no
what does glycolysis produce during aerobic respiration
2 pyruvate
2 ATP
2 reduced NAD/ NADH
.
steps of glycolysis
phosphorylation of glucose:
uses 2 ATP to provide 2 P
produces 2 triose phosphate
and 2 ADP
oxidation of triode phosphate:
triose phosphate loses H
forms 2 pyruvate
H+ collected by 2 NAD
NAD reduced to form 2 NADH
4 ATP produced
in glycolysis, why is the net gain of ATP 2
4 produced
but 2 were used yo phosphorylate glucose
what does pyruvate contain?
chemical energy
how does pyruvate travel from the cytoplasm to the mitochondrial matrix
active transport
what does the link reaction produce per glucose
2 acetyle CoA
2 CO2
2 NADH
steps of the link reaction
pyruvate oxidised (H removed) to form acetate
pyruvate decarboxylated (CO2 removed)
H used to reduce NAD to NADH
acetate combines w coenzyme A to form acetyl CoA
how many carbons in pyruvate
3
how many carbons in acetyl CoA
2
how many carbons in oxaloacetate
4
how many carbons in citrate
6
krebs cycle steps
acetyl CoA accepted by oxaloacetate (4C) to form citrate (6C)
coenzyme A released to be used in next link reaction
oxaloacetate regeneration thru a series of redox reactions:
decarboxylation of citrate releasing 2 CO2
oxidation (dehydrogenation) of citrate releasing H that reduces NAD and FAD
substrate linked phosphorylation forms 1 ATP
what do 2 cycles of the krebs cycle produce
2 ATP
6 NADH
2 FADH2
4 CO2
oxidative phosphorylation steps
H donated by NADH and FADH2, and split into a proton and electron
high energy e- enter e- transport chain and release energy as they pass thru it
energy released used to transport protons across inner mito membrane from matrix to inter membrane space
conc grad of protons established between matrix and inter membrane space
protons return to matrix via facilitated diffusion thru channel enzyme ATP synthase
movement of protons down conc grad provides energy for ATP synthesis
oxygen acts as the final e- acceptor and combines with protons and electrons at the end of the e- transport chain to form water
what is the e- transport chain made up of
a series of membrane proteins/ e- carriers positioned close together
is the mito inner membrane permeable to protons
no
in oxidative phosphorylation, how many ATP produced for every NADH
3
in oxidative phosphorylation, how many ATP produced for every FADH2
2
in aerobic respiration, how many ATP produced per glucose
38
in anaerobic respiration, how is lactate formed
NADH transfers H to pyruvate to form lactate
pyruvate reduced
by lactate dehydrogenase
small amt of ATP produced
in anaerobic respiration, what are the 2 things that can happen to lactate after building up in cells after time
oxidised back to pyruvate
channelled into Krebs cycle for ATP production
or
converted into glucose by liver cells
for respiration use or storage as glycogen
in anaerobic respiration, what occurs when lactate is oxidised back to pyruvate
oxygen debt
as it needs extra oxygen
animals breathe deeper and faster
What are tendons
Strong connective tissue that connects muscles to bones
What are ligaments
Strong connective tissue that connect bone to bone
What is antagonistic muscle action
2 muscles work together by pulling in opposite directions
do muscle fibres have more than one nucleus
yes
what is the muscle fibre cell surface membrane called
sarcolemma
what is the muscle fibre cytoplasm called
sarcoplasm
what is the muscle fibre endoplasmic reticulum called
sarcoplasmic reticulum (sr)
what are T tubules
deep tube like projections folding in from the sarcolemma
run close to the sr
help spread electrical impulses through muscle fibre
what does the sarcoplasm contain
mitochondria and myofibrils
why do the membranes of the sarcoplasmic reticulum contain protein pumps
to transport calcium ions to the lumen of the sr
which are needed for muscle contraction
what is each myofibril made up of
thick myosin filaments
thin actin filaments
what is the H band
only thick myosin filaments present
what is the I band
only thin actin filaments present
what is the A band
areas with only myosin, and areas where myosin and actin overlap
what is the M line
attachement for myosin filaments
what is the Z line
attachment for actin filaments
what is the sarcomere
section of myofibril between 2 Z lines
what is the contraction speed for fast twitch muscle fibres
rapid
short contraction- relaxation cycle
what is the contraction speed for slow twitch muscle fibres
slow
long contraction- relaxation cycle
do fast or slow twitch muscle fibres have a denser capillary network
slow
how do fast twitch muscle fibres generate ATP
anaerobic respiration
how do slow twitch muscle fibres generate ATP
aerobic respiration
do fast or slow twitch muscle fibres have more mitochondria
slow
do fast or slow twitch muscle fibres have more calcium ions in the SR
fast
do fast or slow twitch muscle fibres have more glycogen
fast
do fast or slow twitch muscle fibres have faster rate of ATP hydrolysis in myosin heads
fast
do fast or slow twitch muscle fibres cause rapid fatigue because of lactic acid formation
fast
what is the colour of fast twitch muscle fibres
pale
cos less myoglobin
what is the colour of slow twitch muscle fibres
dark red
cos more myoglobin
where are fast twitch muscle fibres found in humans
eyelids
where are slow twitch muscle fibres found in humans
back muscles
example of activity that uses slow twitch muscle fibres
walking
example of activity that uses fast twitch muscle fibres
weight lifting
function of a respirometer
measures rate of oxygen consumption during aerobic respiration in organisms
function of soda lime/ KOH/ NaOH in respirometer
removes CO2 produced by cellular respiration
function of gauze platform in respirometer
protects organism from contact w corrosive soda lime/ KOH/ NaOH
function of capillary u tube w fluid in respirometer
fluid moves upwards due to change in air pressure as O2 consumed
how to calculate volume of O2 consumed in cm3 min-1
with a respirometer
pi r^2 h
r is cap tube diameter
h is distance moved by fluid in a minute
myosin structure
fibrous protein molecules
globular head
many myosin lie next to each other
globular heads pointing away from M line
actin structure
globular protein molecules
many actins link together to form a chain
2 chains twist together to form 1 filament
fibrous protein tropomyosin twisted around 2 actin chains
troponin attached to chains at regular intervals
sliding filament theory
action potential at neuromuscular junction
Ca+ released from SR
Ca+ bind to troponin
troponin changes shape
causing tropomyosin shape to be altered
exposing myosin binding sites
myosin heads can bind to binding sites
cross bridges form
myosin changes shape, head dips forward
actin filaments slide over myosin, towards M line
sarcomeres shorten
ATP hydrolysed
what happens once muscle stimulation stops
Ca+ leave binding sites on troponin
actively transported to SR
troponin return to og shape
tropomyosin block myosin binding sites
what is meant by the heart is myogenic
beats without any external stimuli
what is the sinoatrial node (SAN)
group of cells in the right atrium wall
what is the atrioventricular node (AVN)
region of conducting tissue between atria and ventricles
what is a bundle of His
collection of conducting tissue in the septum
what is Purkyne tissue
2 conducting fibres that the bundle of His divide into
spread around the ventricles
what are the stages of the cardiac cycle
SAN sends out a wave of excitation
atria contact
AVN sends out a wave of excitation along to bundle of His
Purkyne tissue conducts the wave of excitation
initiates depolarisation of vents from apex
ventricles contract from bottom up, blood forced into pulmonary artery and aorta
what stops depolarisation spreading straight from the atria to the ventricles
a region of non conducting tissue
what is cardiac output
volume of blood pumped by the heart per unit time
why do fitter people have a higher cardiac output
thicker and stronger ventricular muscles
why does cardiac output increase during exercise
so blood supply can match the increased metabolic demand of cells
what is heart rate
the number of times a heart beats per minute
what is stroke volume
the volume of blood pumped out of the left ventricle during one cardiac cycle
what is the formula for calculating cardiac output
cardiac output = heart rate x stroke volume
what do ECGs stand for
electrocardiograms
what are ECGs used for
diagnosing heart problems
what does a bigger wave in an ECG mean
bigger electrical activity passing thru heart
stronger contraction
in an ECG, what happens during the P wave
depolarisation of atria
atrial systole
in an ECG, what happens during the QRS complex
depolarisation of vents
ventricular systole
in an ECG, why is the QRS wave the largest wave
ventricles have the largest muscle mass
in an ECG, what happens during the T wave
repolarisation of vents
ventricular diastole
in an ECG, what happens during the U wave
repolarisation of Purkyne fibres
what is tachycardia
heart beat is too fast
resting above 100 bpm
what is bradycardia
heart beat is too slow
resting below 60 bpm
what is an ectopic heart beat
early heart beat then a pause
earlier contraction of atria/ vents
what is fibrillation
irregular heart beat
atria/ vents stop contracting properly
severe can be fatal
