Paper 3 Flashcards
1
Q
Chloride Shift
A
- CO2 in rbc can turn into carboaminohaemoglobin or carbonic acid
- carbonic acid can be broken down by carbonic anhydrase into H ions and hydrogen carbonate
- hydrogen carbonate then leaves the red blood cell and to balance the electrochemical gradient chloride moves in
- the H ions then are removed by buffers especially haemoglobin (forms haemoglobinic acid
2
Q
Oncotic pressure
A
- plasma proteins are too large to leave capillary
- so low water potential (lower than tissue fluid)
- moves by osmosis down WP gradient back into capillary
3
Q
Arteries
A
- heart to the rest of the body
- small lumen
- high pressure
- thick muscular, elastic walls
- mainly carry oxygenated blood
4
Q
Tissue fluid contents
A
- few white blood cells
- very few proteins
- dissolved solutes
- water
5
Q
Lymph contents
A
- white blood cells
- only antibodies
- water
- dissolved solutes
6
Q
Veins
A
- take blood back to the heart
- low pressure
- deoxygenated blood
- wider lumen
- contain valves
7
Q
tachycardia
A
- too fast
8
Q
bradycardia
A
- too slow
9
Q
ectopic
A
- extra heart beat
10
Q
atrial fibrillation
A
- abnormal rhythm
11
Q
Bohr shift
A
- curve moves to the right
- more co2
- at the same partial pressure of 02 Hb has a lower saturation of 02
- more o2 dissociates from Hb more readily
- more o2 for aerobic respiration
12
Q
Cardiac graph
A
- bottom left = AV opens
- top left = SLV opens
- top right = SLV closes
- bottom right = AV closes
13
Q
Lub
A
- blood forced against AV valves as ventricle contact
14
Q
Dub
A
- back flow of blood closes SL valves as ventricles close
15
Q
facilitated diffusion
A
- for high to low
- down a concentration gradient
- ion = channel proteins
- large molecules = carrier proteins
16
Q
Hypothalamus
A
- middle of the brain
- maintains body temperature and produces hormones
17
Q
Pituitary gland
A
- releases hormones and stimulates other glands
18
Q
sodium potassium pump
A
- pumps 3NA out the cells
- 2K ions into the cell
- uneven distribution of charge, more negative inside the cell
- sodium channels are closed
- potassium channels are open
- inorganic ions keep the inside more negative
19
Q
depolarisation
A
- Na channels open the NA ions move into to cell down their concentration gradient
- changes change in the potential difference across the membrane
- inside becomes more positive (above threshold)
20
Q
repolarisation
A
- voltage gated K ion channels open and sodium channels close
- more negative inside the cell
- k ions diffuse out
21
Q
hyperpolarised
A
- potential difference become more negative than resting potential
22
Q
refractory period
A
- potassium channels close and sodium/potassium pumps restore distribution
- sodium channels stay closed
- ensure action potential only goes one way
- ensure action potential doesn’t overlap but occurs as a discrete impulses
23
Q
synapse
A
- junction between neurones and another
- when action potential reaches the threshold value causes calcium gated channels to open
- increasing the conc. of calcium inside the knob
- causes vesicles to undergo exocytosis releasing Ach into the synaptic cleft
- Ach binds to sodium channel receptors of the post synaptic neurones and causing the action potential to travel to the next neurones
- acetylcholinesterase breaks down Ach into ethanoic acid and choline
24
Q
role of synapes
A
- excitatory = depolarisation of post synaptic cleft (ACH)
- inhibitory = hyperpolarisation action, no action potential occurs (GABA)
- spatial = neurotransmitter builds up to reach threshold value
- temporal = build up so the synapse is sufficient to cause a action potential
25
transmission of impulse
- flow of current carried along by the flow of positive ions
- decays due to resistance provided by cytoplasm
- has to be boosted at individual intervals so it propagated along the neuron
- sped up by = axon diameter
= temperature
= myelin sheath
26
myelinated neurones
- action potential jumps from node to node
- nodes of Ranvier intervals are 1-3mm
- nodes are very shorts = 2-3 micrometers
-speed = 100-120 m/s
- long neurons carry messages quickly over long distances
27
non- myelinated neurones
- non nodes of Ranvier
- action potential moves along neurone in a wave
- speed = 1m/s
- tend to be shorter neurones
- short distances (breathing and digestion)
28
smooth muscle
- spindle like shaped
- uninucleate
- not striated
- involuntary
29
cardiac muscle
- myogenic
- striated
- branching
- intercalated disc
- uninucleate
30
skeletal muscle
- striated
- multinucleated
- many mitochondria
- voluntary
31
parts of the sliding filament model
- I band = light band (actin only)
- A band = dark band (overlap of actin and myosin and myosin)
- H zone = only myosin filaments
- Z line = end of sarcomere
- M line = center of H-zone
32
Tropomyosin
- long chain protein that blocks the binding site of myosin to actin
33
troponin
- 3 binding sites
- actin, tropomyosin, calcium ions
34
Sliding filament model
- tropomyosin prevents myosin binding to actin
- calcium ions than bind to troponin causing is to change shape and revealing the myosin binding site
- myosin head can now bind to the actin filament forming cross bridge
- head of myosin changes it angle moving the actin filament along (ADP is produces)
- ATP causing the myosin head to detach form the actin filament
- cycle repeats
35
slow twitch
- contract slowly
- aerobic respiration
- large amounts of energy released
- large store of myoglobin
- less powerful contractions
- SO muscle fibre types
36
fast twitch
- contract very quickly
- gain energy from anaerobic respiration
- powerful contractions
- used for speed
-more myosin and thicker filaments
37
Pacinian corpuscle
- contains stretch mediated sodium ion channels
- no pressure = resting potential
-when pressure is applied channel changes shape widening the sodium channels
- sodium diffuses into the neurones
- changing the potential of the membrane ( generator potential in created)
38
Spatial summation
- many presynaptic neurones connect to one postsynaptic neurone
39
temporal summation
- one presynaptic neurone releases neurotransmitter as a result of an action potential several times over a short period of time
40
Peripheral nervous system
- autonomic and somatic
- connects CNS to the rest of the body
- by sensory and motor neurones
41
Autonomic nervous system
- under subconscious control
- HR
- divided into sympathetic and parasympathetic system
42
Somatic nervous system
- under conscious control
-carries impulses to body muscles
