run for your life Flashcards
(196 cards)
1
Q
is ATP water soluble
A
yes
has polar groups
2
Q
what type of reaction forms ADP and Pi from ATP
A
hydrolysis
3
Q
what type of reaction forms ATP from ADP and Pi
A
phosphorylation
4
Q
what is respiration
A
process of breaking down a respiratory substrate in order to produce ATP using oxygen
5
Q
examples of a respiratory substrate
A
glucose
fatty acids
amino acids
6
Q
what is the energy formed from respiration used for
A
to phosphorylate ADP to form ATP
7
Q
what are the stages of aerobic respiration
A
- glycolysis
- the Link reaction
- the Krebs cycle
- oxidative phosphorylation
8
Q
what are NAD and FAD
A
coenzymes
responsible for transferring H between molecules
can reduce/ oxidise molecules
9
Q
what is coenzyme A
A
responsible for transfer of acetate
10
Q
mitochondria outer membrane
A
smooth
permeable to several small molecules
11
Q
mitochondria inner membrane
A
folded (into cristae)
less permeable
site of electron transport chain used in oxidative phosphorylation
location of ATP synthase enzymes
12
Q
mitochondria inter membrane space
A
low pH cos go high conc of protons
conc grad formed during oxidative phosphorylation
which is essential for ATP synthesis
13
Q
mitochondria matrix
A
aqueous sol within inner membrane
contains ribosomes, enzymes, circular mitochondrial DNA
14
Q
where does glycolysis occur
A
cytoplasm
15
Q
where does the Link reaction occur
A
matrix of mitochondria
16
Q
where does the Krebs cycle occur
A
matrix of mitochondria
17
Q
where does oxidative phosphorylation occur
A
inner membrane of mitochondria
18
Q
does glycolysis require oxygen
A
no
19
Q
what does glycolysis produce during aerobic respiration
A
2 pyruvate
2 ATP
2 reduced NAD/ NADH
20
Q
steps of glycolysis
A
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
21
Q
in glycolysis, why is the net gain of ATP 2
A
4 produced
but 2 were used yo phosphorylate glucose
22
Q
what does pyruvate contain?
A
chemical energy
23
Q
how does pyruvate travel from the cytoplasm to the mitochondrial matrix
A
active transport
24
Q
what does the link reaction produce per glucose
A
2 acetyle CoA
2 CO2
2 NADH
25
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
26
how many carbons in pyruvate
3
27
how many carbons in acetyl CoA
2
28
how many carbons in oxaloacetate
4
29
how many carbons in citrate
6
30
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
31
what do 2 cycles of the krebs cycle produce
2 ATP
6 NADH
2 FADH2
4 CO2
32
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
33
what is the e- transport chain made up of
a series of membrane proteins/ e- carriers positioned close together
34
is the mito inner membrane permeable to protons
no
35
in oxidative phosphorylation, how many ATP produced for every NADH
3
36
in oxidative phosphorylation, how many ATP produced for every FADH2
2
37
in aerobic respiration, how many ATP produced per glucose
38
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
39
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
40
in anaerobic respiration, what occurs when lactate is oxidised back to pyruvate
oxygen debt
as it needs extra oxygen
animals breathe deeper and faster
41
What are tendons
Strong connective tissue that connects muscles to bones
42
What are ligaments
Strong connective tissue that connect bone to bone
43
What is antagonistic muscle action
2 muscles work together by pulling in opposite directions
44
do muscle fibres have more than one nucleus
yes
45
what is the muscle fibre cell surface membrane called
sarcolemma
46
what is the muscle fibre cytoplasm called
sarcoplasm
47
what is the muscle fibre endoplasmic reticulum called
sarcoplasmic reticulum (sr)
48
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
49
what does the sarcoplasm contain
mitochondria and myofibrils
50
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
51
what is each myofibril made up of
thick myosin filaments
thin actin filaments
52
what is the H band
only thick myosin filaments present
53
what is the I band
only thin actin filaments present
54
what is the A band
areas with only myosin, and areas where myosin and actin overlap
55
what is the M line
attachement for myosin filaments
56
what is the Z line
attachment for actin filaments
57
what is the sarcomere
section of myofibril between 2 Z lines
58
what is the contraction speed for fast twitch muscle fibres
rapid
short contraction- relaxation cycle
59
what is the contraction speed for slow twitch muscle fibres
slow
long contraction- relaxation cycle
60
do fast or slow twitch muscle fibres have a denser capillary network
slow
61
how do fast twitch muscle fibres generate ATP
anaerobic respiration
62
how do slow twitch muscle fibres generate ATP
aerobic respiration
63
do fast or slow twitch muscle fibres have more mitochondria
slow
64
do fast or slow twitch muscle fibres have more calcium ions in the SR
fast
65
do fast or slow twitch muscle fibres have more glycogen
fast
66
do fast or slow twitch muscle fibres have faster rate of ATP hydrolysis in myosin heads
fast
67
do fast or slow twitch muscle fibres cause rapid fatigue because of lactic acid formation
fast
68
what is the colour of fast twitch muscle fibres
pale
cos less myoglobin
69
what is the colour of slow twitch muscle fibres
dark red
cos more myoglobin
70
where are fast twitch muscle fibres found in humans
eyelids
71
where are slow twitch muscle fibres found in humans
back muscles
72
example of activity that uses slow twitch muscle fibres
walking
73
example of activity that uses fast twitch muscle fibres
weight lifting
74
function of a respirometer
measures rate of oxygen consumption during aerobic respiration in organisms
75
function of soda lime/ KOH/ NaOH in respirometer
removes CO2 produced by cellular respiration
76
function of gauze platform in respirometer
protects organism from contact w corrosive soda lime/ KOH/ NaOH
77
function of capillary u tube w fluid in respirometer
fluid moves upwards due to change in air pressure as O2 consumed
78
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
79
myosin structure
fibrous protein molecules
globular head
many myosin lie next to each other
globular heads pointing away from M line
80
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
81
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
82
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
83
what is meant by the heart is myogenic
beats without any external stimuli
84
what is the sinoatrial node (SAN)
group of cells in the right atrium wall
85
what is the atrioventricular node (AVN)
region of conducting tissue between atria and ventricles
86
what is a bundle of His
collection of conducting tissue in the septum
87
what is Purkyne tissue
2 conducting fibres that the bundle of His divide into
spread around the ventricles
88
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
89
what stops depolarisation spreading straight from the atria to the ventricles
a region of non conducting tissue
90
what is cardiac output
volume of blood pumped by the heart per unit time
91
why do fitter people have a higher cardiac output
thicker and stronger ventricular muscles
92
why does cardiac output increase during exercise
so blood supply can match the increased metabolic demand of cells
93
what is heart rate
the number of times a heart beats per minute
94
what is stroke volume
the volume of blood pumped out of the left ventricle during one cardiac cycle
95
what is the formula for calculating cardiac output
cardiac output = heart rate x stroke volume
96
what do ECGs stand for
electrocardiograms
97
what are ECGs used for
diagnosing heart problems
98
what does a bigger wave in an ECG mean
bigger electrical activity passing thru heart
stronger contraction
99
in an ECG, what happens during the P wave
depolarisation of atria
atrial systole
100
in an ECG, what happens during the QRS complex
depolarisation of vents
ventricular systole
101
in an ECG, why is the QRS wave the largest wave
ventricles have the largest muscle mass
102
in an ECG, what happens during the T wave
repolarisation of vents
ventricular diastole
103
in an ECG, what happens during the U wave
repolarisation of Purkyne fibres
104
what is tachycardia
heart beat is too fast
resting above 100 bpm
105
what is bradycardia
heart beat is too slow
resting below 60 bpm
106
what is an ectopic heart beat
early heart beat then a pause
earlier contraction of atria/ vents
107
what is fibrillation
irregular heart beat
atria/ vents stop contracting properly
severe can be fatal
108
why is it important for temperature to be controlled by homeostasis
temps above 40 denature enzymes
high kinetic energy breaks H bonds in tertiary structure
active site shape changes
no longer complimentary to substrate
enzyme substrate complex cant form
less efficient metabolic reactions
109
why is it important for blood glucose levels to be controlled by homeostasis
glucose required to supply ATP for energy
110
what monitors blood glucose levels
cells in the pancreas
111
why is it important for blood water to be controlled by homeostasis
amt of blood in water needs to stay constant
makes up cytoplasm
takes part in metabolic reactions
112
what regulates blood water levels
kidneys
113
how is water lost from the body
excretion of waste products eg urine, sweat
114
what is thermoregulation
maintenance of a constant internal body temperature
115
what are the cooling mechanisms of thermoregulation
vasodilation
sweating
flattening of hairs
116
how does vasodilation work in thermoregulation
arteriole wall muscles relax
arterioles dialate
more blood flows through skin capillaries
increasing heat loss to the environment
117
how does sweating work in thermoregulation
sweat secreted by sweat glands
cools skin by evaporation
118
why is sweating less effective in humid environments
sweat evaporates more slowly due to a reduced concentration gradient between the sweat and the surrounding air
119
how does flattening of hairs work in thermoregulation
hair erector pili muscles in skin relax
hairs lie flat
no insulating layer of trapped air
air can circulate over skin
heat can leave by radiation
120
what are the warming mechanisms of thermoregulation
vasoconstriction
boosting metabolic rate
shivering
erection of hairs
less sweating
121
how does vasoconstriction work in thermoregulation
arteriole wall muscles contract
arterioles near skin constrict
less blood flows thru skin caps
blood diverted to shunt vessels
(deeper in skin so dont lose heat to environment)
122
how does boosting metabolic rate work in thermoregulation
most metabolic reactions r exo
hormone thyroxine increases BMR
so increases heat production in body
adrenaline also released
123
how does shivering work in thermoregulation
reflex action in response to decrease in core body temp
muscles contract in a rapid regular movement
metabolic reactions needed to power shivering generate heat
warms blood increases core body temp
124
how does erection of hairs work in thermoregulation
hair erector pili muscles in skin contract
hairs stand on end
traps air
forms insulating layer over skin
125
how does less sweating work in thermoregulation
sweat glands release less sweat
less heat lost thru evaporation of sweat
126
is shivering a hormonal or nervous mechanism
nervous
127
what is the hypothalamus responsible for controlling
hormones
sleep
growth
body temp
blood pressure
128
what receptors do mammals detect external temperatures via
thermoreceptors
129
where are thermoreceptors found in mammals
skin
mucous membranes
130
what does the hypothalamus monitor to help regulate body temperature
the temperature of the blood flowing through it
131
what does negative feedback do
reverse a change in the body to bring it back within normal limits
132
what does negative feedback do if there is an increase in a physiological factor
make the body respond to make the factor decrease
133
what does negative feedback do if there is a decrease in a physiological factor
make the body respond to make the factor increase
134
in negative feedback, what happens to the level of correction as the physiological factor gets closer to its normal value
level of correction decreases
135
what is positive feedback
when the original stimulus produces a response that causes the factor to deviate even more from the normal range
136
example of positive feedback
dilation of the cervix during labour
blood clotting to close up a wound
137
why is positive feedback not involved in homeostasis
does not maintain a constant internal environment
138
how can hormones alter events inside a cell
by influencing gene expression
139
what do eukaryotes use to control gene expression
transcription factors
140
what is a transcription factor
protein that controls transcription of genes by binding to specific regions of DNA
141
what do transcription factors ensure
that genes r expressed:
in correct cells
at correct time
to the right level
142
what are activators
transcription factors that increase the rate at which a gene is expressed
143
what are repressors
transcription factors that decrease the rate at which a gene is expressed
144
examples of hormones that can cross the cell surface membrane
steroid hormones
thyroid hormones
145
how do hormones affect gene expression inside cells
enter nucleus
bind to transcription factors present there
146
examples of hormones that can't cross the cell surface membrane
adrenaline
insulin
glucagon
ADH
147
how do hormones affect gene expression outside cells
bind to receptors in cell surface membrane
initiates process that activates second messengers in cytoplasm
these activate enzymes called protein kinases
these trigger a chain of reactions called a cascade
may result in changes to the activity of transcription factors
may affect gene expression
148
why do cells require more energy during exercise
muscle contraction occurs more frequently
149
why does the body increase the rate and depth of breathing during exercise
more oxygen enters lungs and bloodstream
gets rid of more CO2
150
why does the body increase the heart rate during exercise
transports oxygen to muscles faster
151
what controls breathing rate
ventilation centres in the medulla oblongata
152
what does the inspiratory centre control
movement of air into the lungs
153
what does the expiratory centre control
movement of air out of the lungs
154
where are the inspiratory and expiratory centres
medulla oblongata
155
what is the process of inhalation
inspiratory centre sends nerve impulses along motor neurones to intercostal and diaphragm muscles
muscles contract
chest volume increases
air pressure in lungs decreases to slightly below atmospheric pressure
impulse sent to expiratory centre to inhibit its action
air flows into lungs cos pressure is lower than outside air
156
what happens when the lungs inflate
stretch receptors in lungs stimulated
nerve impulse sent to medulla oblongata that inhibits inspiratory centre
expiratory centre no longer inhibited
157
what is the process of exhalation
expiratory centre sends nerve impulses to intercostal and diaphragm muscles
muscles relax
chest volume decreases
air pressure in lungs increases to slightly above atmospheric pressure
air flows out of lungs
158
what happens when the lungs deflate
stretch receptors inactive
inspiratory centre no longer inhibited
next breathing cycle begins
159
during exercise, what happens to the extra CO2 produced
dissolves in blood
forms carbonic acid
dissociated into protons and hydrogencarbonate ions
blood becomes more acidic
160
what receptors detect the decrease in blood pH during exercise
chemoreceptors
161
where are chemoreceptors found
in ventilation centre of medulla oblongata
also present as clusters of cells in the aorta (aortic bodies) and the carotid arteries (carotid bodies)
162
what happens when a decrease in blood pH is detected
nerve impulse sent to medulla oblongata
which sends more frequent nerve impulses to intercostal and diaphragm muscles
increasing rate and strength of contractions
increasing breathing rate and depth
more O2 enters lungs so more CO2 exhaled and removed from blood
blood pH returns to normal so breathing rate returns to normal
163
what is ventilation rate
the volume of air that moves in and out of the lungs during a set time period
164
what controls heart rate
cardiovascular control centre in medulla oblongata
which controls the rate at which the SAN generates electrical impulses
165
what receptors detect stimuli that can change heart rate
baroreceptors
chemoreceptors
166
where are baroreceptors found
carotid bodies
aortic bodies
167
what are baroreceptors stimulated by
high and low blood pressure
168
what happens once receptors detect stimuli that can change heart rate
send impulses to cardiovascular control centre
which sends impulses to SAN along sympathetic or parasympathetic neurones
169
what do sympathetic neurones do to the SAN
increase the rate at which SAN generates electrical impulses
increases heart rate
170
what do parasympathetic neurones do to the SAN
decrease the rate at which SAN generates electrical impulses
decrease heart rate
171
what does the sympathetic nervous system do
prepare body for action
increase heart during exercise
172
what does the parasympathetic nervous system do
calm body down after action
decrease heart rate after exercise
173
how does the heart respond to high blood pressure
detected by baroreceptors
send impulses to cardiovascular control centre
sends impulses along parasympathetic neurones
secrete neurotransmitter acetycholine
binds to receptors on SAN
SAN fires less frequently
heart rate decreases, blood pressure decreases to normal
174
how does the heart respond to low blood pressure
detected by baroreceptors
send impulses to cardiovascular control centre
sends impulses along sympathetic neurones
secrete neurotransmitter noradrenaline
binds to receptors on SAN
SAN fires more frequently
heart rate increases, blood pressure increases to normal
175
how does the heart respond to high blood oxygen, low CO2, high pH levels
detected by chemoreceptors
send impulses to cardiovascular control centre
sends impulses along parasympathetic neurones
secrete neurotransmitter acetylcholine
binds to receptors on SAN
SAN fires less frequently
heart rate slows down and O2, CO2, pH return to normal
176
how does the heart respond to low blood oxygen, high CO2, low pH levels
detected by chemoreceptors
send impulses to cardiovascular control centre
sends impulses along sympathetic neurones
secrete neurotransmitter noradrenaline
binds to receptors on SAN
SAN fires more frequently
heart rate increases and O2, CO2, pH return to normal
177
what is tidal volume
vol of air breathed in/ out at rest
178
what is breathing rate
number of breaths taken in a minute
179
what is oxygen consumption
vol of O2 used up in a given time
180
what is respiratory minute ventilation
vol of air that can be breathed in/ out in a min
181
formula for respiratory minute ventilation
tidal vol x breathing rate
182
how does a spirometer work
person breathes thru it
soda lime absorbs CO2
trace drawn/ graph formed
183
what are the effects of excercising too little
increased risk of obesity
cardiovascular disease (CVD)
diabetes
184
what are the effects of excercising too much
wear and tear on joints
suppression of the immune system
185
how does keyhole surgery work
small incision made in skin
(less invasive)
camera and special medical instruments inserted into incision
186
what are some advantages of keyhole surgery compared to conventional surgery
less blood and scarring
less pain after surgery so quicker recovery so shorter hospital stay
187
how is a damaged cruciate ligament fixed with keyhole surgery
ligament removed
replaced by graft of tendon
from donor or other tendon in patients leg
188
what is the cruciate ligament
middle of knee
connects thigh bone
to lower leg bone
189
what do prostheses replace
missing/ damaged body parts
entire or parts of limbs
190
what are some prostheses connected to
electronic devices
that can read info from nervous system
to operate body part
191
how is a damaged knee joint fixed with a prosthesis
damaged cartilage and bone replaced by metal device on both long bones
to create a smooth surface for articulation
plastic spacer inserted between metal ends of prosthesis to provide cushioning and reduce impact on the knee
192
what are different types of performance enhancing drugs
anabolic steriods
increase muscle size, strength
but organ damage and aggression
stimulants
increase reaction times, endurance
but agression
narcotic analgesics
strong painkillers allow them to maintain performance despite injuries
193
what do rationalists believe about performance enhancing drugs in sports
there may be times when their use is justified
194
what do absolutists believe about performance enhancing drugs in sports
they are morally wrong and should be banned from all sport
195
arguments for performance enhancing drugs in sports
athletes have freedom to choose if they wanna deal w the risks
may help overcome inequalities
some may only be able to compete at higher level w drugs
196
arguments against performance enhancing drugs in sports
illegal
unfair advantage
serious health risks
unsure if athletes r fully informed ab risks
