anatomy Flashcards
describe the flow of blood through the heart
•superior/inferior vena cava
•right atrium
•tricuspid valve
•right ventricle
•pulmonary semi lunar valve
•pulmonary arteries
•lungs
•pulmonary veins
•left atrium
•biscupid valve
•left ventricle
•aortic semi lunar valve
•aorta
describe the two types of circuits in the vascular system
•pulmonary: deoxygenated blood from heart to lungs and oxygenated blood back to heart
•systemic: oxygenated blood to the body from the heart and return of deoxygenated blood from the body to the heart
describe the structure of the five types of blood vessel
•arteries: thick muscle/elastic tissue layers, small lumen, smooth inner layer, high blood pressure
•veins: low blood pressure, valves, wide lumen, thin muscle/ elastic tissue layers
•capillaries: allowed for exchange of nutrients one cell thick
•arterioles: thick muscle walls,
thin lumen
•venules: small lumen, thinner walls than arterioles
define systolic and diastolic blood pressure
heart contracts = systolic blood pressure (high)
heart relaxes = diastolic blood pressure (low)
explain the relationship between blood pressure and location
high blood pressure in arteries
low blood pressure in veins
low blood pressure in capillaries
define blood pressure
force of blood against the blood vessel walls
define atherosclerosis
arteries blocked by atheroma
define atheroma
(a build up of) fatty deposits
define angina
when oxygen cannot be provided to the heart
define low density lipoproteins
transport bad cholesterol into the blood and tissue
define high density lipoproteins
removes excess cholesterol from blood and transports to liver where it can be broken down
define stroke
blood supply to brain is cut off + brain cells die
identify the negative impacts of a lack of physical activity on the cardiovascular system
•high blood pressure
•high cholesterol
•heart disease
•stroke
explain the effects of the negative impacts of a lack of physical activity of the cardiovascular system
•puts extra strain on arteries and heart - can lead to heart attack, heart failure, kidney disease, stroke, dementia
•increased risk of heart disease, low density lipoproteins
•arteries that supply heart muscles with oxygenated blood become blocked/narrow (atherosclerosis)
explain the benefit of regular physical activity on the negative impacts
•regular exercise can lower systolic and diastolic pressure
•exercise lowers LDL cholesterol and increases HDL cholesterol levels
•keeps the heart healthy and efficient (hypertrophy - can pull more blood around the body)
define stroke volume
the volume of blood pumped out of the heart’s left ventricle during each systolic contraction
define cardiac output (Q)
the quantity of blood pumped by the heart within a minute
define heart rate
the number of times the heart beats within a minute
define venous return
the flow of blood from the periphery (body) back to the right atrium
define ejection fraction
the percentage of blood pumped out by the left ventricle per beat
define cardiac hypertrophy
the thickening of the muscular wall of the heart so it becomes bigger and stronger; also can mean a larger ventricular cavity
define bradycardia
a decrease in resting heart rate to below 60bpm —> amount of blood pumped out (divided by) amount of blood in
Describe the factors that determine stroke volume
•venous return
•elasticity of cardiac fibres - the more the fibres can stretch (during diastolic phase) the greater the force of contraction
•controllability of cardiac tissue - the greater the controlability, the greater the force
describe what is meant by Starling’s Law
increased venous return —> greater diastolic filling of the heart —> cardiac muscle stretched —> greater force of contraction —> increased ejection fraction
explain the changes in heart rate during maximal exercise
•anticipatory rise due to adrenaline
•sharp rise in HR due to mainly anaerobic work
•HR continues to rise due to maximal work loads
•rapid decline in HR due to exercise stopping
•slow recovery as systems return to resting levels
explain the changes to heart rate during submaximal exercise
•anticipatory rise due to adrenaline
•sharp rise in HR due to mainly aerobic work
•steady state as athlete is able to meet oxygen demand with oxygen supply
•rapid decline in heart rate do to exercise stopping
•slow recovery as systems return to resting levels
explain the changes to cardiac output (Q) in response to exercise
•Increase in HR + SV= increase in Q
• Heart rate will increase in proportion to intensity
> max HR is reached
Explain the changes to stroke volume in response to exercise
• SV increases with intensity
• Only to 40-60% of maximun
•SV plateaus due to increased HR - shorter diastolic phase
• Not enough time for heart to fill with blood so cannot pump as much out.
=>regular training - resting SV increases
define medulla oblongata
the most important part of the brain as it regulates processes that keep us alive such as breathing and heart rate
define myogenic
the capacity of the heart to generate its own impulses
define sino-atrial node (SAN)
a small mass of cardiac muscle found in the wall of the right atrium that generates the heartbeat (commonly called the pacemaker)
define atrioventricular node (AVN)
this node relays the impulse between the upper and lower sections of the heart
define systole
when the heart contracts
define diastole
when the heart relaxes
bundle of His
a collection of heart muscle cells that transmit electrical impulses from the AVN via the bundle branches to the ventricles
define purkinje fibres
muscle fibres that conduct impulses in the walls of the ventricles
describe the sympathetic and parasympathetic nervous systems
sympathetic: a part of the autonomic nervous system that speeds up the heart rate
parasympathetic: a part of the autonomic nervous system that decreases heart rate
identify the three types of receptor and explain their roles
•chomereceptors - tiny structures (in the carotid arteries and aortic arch) that detect changes in blood acidity e.g. increase in CO2
•baroreceptors - special sensors in tissues (in the aortic arch, carotid sinus, heart and pulmonary vessels) that respond to changes in blood pressure to either increase or decrease heart rate
•proprioceptors - sensory nerve endings (in muscles, tendons and joint) that detect changes in muscle movement
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after detecting movement, receptors send an impulse to the medulla oblongata (brain which then sends an impulse through sympathetic nervous system to SAN to increase HR)
describe how hormones can have an effect on heart rate
adrenaline released -> stimulates SAN -> increase in speed/ force of contraction -> increase cardiac output by sympathetic nerves
describe the pathway of the impulse through the heart during the cardiac conduction system
the impulses travel from the sino-atrial node (SAN) to the atrioventricular node (AVN). there the impulses slow down for 1 second to allow the blood to flow. then to the bundle of His and the right + left bundle branches to the purkinje fibres surrounding the ventricles.
define steady state
where the athlete is able to meet the oxygen demand with the oxygen supply
what is cardiovascular drift?
cardiovascular drift is characterised by a progressive decrease in stroke volume and blood pressure with a rise in heart rate
why does cardiovascular drift occur?
•prolonged exercise in warm environment - sweating more -> blood plasma volume decreases when we sweat = decrease in venous return and therefore SV (Starling’s Law)
•as a result heart rate increases to compensate and maintain a higher cardiac output
•this attempts to create more energy to cool the body down
MAINTAIN HIGH FLUID CONSUMPTION IN ORDER TO AVOID CARDIOVASCULAR DRIFT
what are the problems with cardiovascular drift
•HR moves towards max = anaerobic system = lactic acid
•early fatigue -> ^ viscosity = decrease in blood flow = decreased O2 to muscles
•heat illness = decreased performance
•energy is used for cooling down = less energy for performance = decreased performance levels
define arteria-venous difference
difference between oxygen content of arterial blood arriving at the muscles and the venous blood leaving muscles
Explain what happens to arterio-venous difference during exercise
Rest: arterio-venous difference is low as not much oxygen is required by the muscles
Exercise: more oxygen is needed from blood for muscles so arterio-venous difference is high
define vascular shunt mechanism
the redistribution of cardiac output
define vasoconstriction
the narrowing of the blood vessels to reduce blood flow to capillaries
define vasodilation
the widening of the blood vessels to increase the flow of blood into the capillaries
describe the change in blood flow to different areas of the body when at rest + during exercise
rest: skeletal muscle - 15-20%
brain - 15%
exercise: skeletal muscle - 80-85% - more energy needed to cool down body
brain - 3-4% (same volume as at rest)
BRAIN MUST REMAIN CONSTANT
explain why there is a change in the distribution of blood during exercise
the skeletal muscles require more oxygen during exercise so more blood needs to be redirected to them in order to meet the increase in demand of oxygen
explain how the vasomotor centre controls blood flow to different areas in the body
chemical changes - increase in CO2/lactic acid detected by the chemoreceptors —> vasomotor centre stimulated which in turn stimulates sympathetic nerves in walls of blood vessels —> vasoconstriction in arterioles supplying non-essential areas of the body/vasodilation in arterioles supplying essential areas of the body
pre-capillary sphincters - contract (vasoconstrict)
expand (vasodilate)
justify the importance of the redistribution of blood
•increases supply of oxygen to working muscles
•removes waste products from the muscles such as CO2 and lactic acid
•ensure more blood goes to the skin during exercise to regulate body temperature and get rid of heat through radiation, evaporation (sweating)
•direct more blood to the heart as it is a muscle and requires extra oxygen during exercise
define plasma
fluid part of blood (surrounds cells + transports them)
define haemoglobin
pigment found in red blood cells - which combine with oxygen (to make oxyhaemoglobin)
define myoglobin
muscle pigment in slow-twitch muscle fibres —> higher affinity than haemoglobin (can hold more)
define mitochondria
respiration + energy production occur here
define pH
a measure of acidity
describe the transportation of oxygen at the lungs
oxygen diffuses into capillaries around alveoli —> 3% dissolves into plasma —> 97% combines with haemoglobin
haemoglobin can carry four oxygen molecules (when fully saturated)
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this occurs when the partial (volume) pressure of oxygen in the blood is high e.g. in the capillaries in lungs
describe the transportation of oxygen at the tissues
•oxygen is released from oxyhaemoglobin - due to low pressure of oxygen in the tissues
•this process is called oxyhaemoglobin dissociation
•oxygen is stored in the myoglobin (in muscle)
•myoglobin has a higher affinity (strength of attraction) than haemoglobin
•myoglobin stores the oxygen until ready for use by mitochondria
describe what occurs during oxyghaemoglobin dissociation at rest + during exercise
at partial pressure of oxygen in the lungs, haemoglobin is almost fully saturated
in the tissues, partial pressure of oxygen is lower therefore haemoglobin gives some of its oxygen to the tissues
this is fine at rest when the muscles do not require much oxygen but during exercise this needs to occur faster so more oxygen in released by haemoglobin
the curve shifts to the right during exercise as muscles require more oxygen.
explain the factors that are responsible for the Bohr shift
•increase in body temperature - blood/muscle temperature increases during exercise. haemoglobin dissociates quicker
•increase in partial pressure of CO2 - as CO2 levels rise, haemoglobin dissociates faster
•decrease in pH in blood - increase in CO2 lowers pH. this drop causes oxygen to dissociate from haemoglobin quicker
define venous return
return of blood to the right side heart via the vena cava
describe the venous return mechanisms
venous return increases during exercise
•skeletal muscle pump (lower body)
•respiratory pump (chest area)
•pocket valves
•gravity (upper body areas + areas above heart)
•smooth inner muscle layer (helps squeeze blood back to heart)
•suction pump of heart (blood drawn back to heart through suction effect if heart pumping blood out)
explain the relationship between venous return and blood pressure
an increase in systolic BP = an increase in VR
determined by a pressure gradient between the right atrium + vena cava
this can be affected by:
•venous pressure
•right atrial pressure
•venous resistance
State the Pathway of air
1) nose/mouth
2) pharynx
3) larynx
4) trachea
5) bronchi
6) bronchioles
7) alveoli
Describe the mechanics of breathing
Inspiration:
1) intercostal muscles + diaphragm contract
2) rib cage pulled up + out
3) increase area inside cavity - room for lungs to inflate
4) decrease pressure inside thoracic cavity
5) air move from environment into lungs - air moves from high to low pressure
Expiration:
1) intercostal muscles + diaphragm relax
2) rib cage down + in
3) decrease area inside cavity - lungs deflate
4) increase pressure inside thoracic cavity
5) air move from lungs to environment - air moves from low to high pressure
Define tidal volume
The volume of air inspired or expired per breath
Define inspiratory reserve volume
Volume of air that can be forcibly inspired after a normal breath
Define expiratory reserve volume
Volume of air that can be forcibly expired after a normal breath
Define residual volume
Amount of air left in the lungs after maximal expiration
Define minute ventilation
Volume of air inspired or expired per minute (number of breaths per min x tidal volume)
Define spirometer
Measures lung volumes
Define vital capacity
Total amount of air expired after maximal inhalation
Describe the changes that occur to each of the lung volumes during exercise
Tidal volume and minute ventilation increase during exercise. As more oxygen needed to working muscles. Performer avoids fatigue - perform better for longer
Define gaseous exchange
Concerned with getting oxygen from air to lungs to blood to cells
Removal of carbon dioxide from blood
Define partial pressure
Pressure exerted by a gas when it exists within a mixture of gases e.g. in air, oxygen exerts a partial pressure
Define diffusion
The movement of gas molecules from an area of high concentration/partial pressure to an area of low concentration/partial pressure
Define concentration/diffusion gradient
Explains how gases flow from high to low gradient, the steeper the gradient, the faster diffusion occurs (difference between concentration levels at high and low areas)
Partial pressure of oxygen and carbon dioxide in capillary and in alveoli
PO_2 in capillary = 40mmHg
PCO_2 in capillary = 46mmHg
PO_2 in alveoli = 104mmHg
PCO_2 in alveoli = 40mmHg
Explain the partial pressure of gases during the process of gaseous exchange at the alveoli
PO_2 is greater in the alveoli than capillary meaning O_2 moves from alveoli to capillary
PCO_2 in capillary is greater than in alveoli meaning CO_2 moves from blood to alveoli
Carbon dioxide is higher in blood because it is given off during exercise
Explain the partial pressures of gases during the process of gaseous exchange at the muscles
PO_2 is less at tissues than in blood for diffusion to occur meaning O_2 diffuses into muscle
PCO_2 in blood is greater than in muscle meaning CO_2 diffuses into blood
Explain how pulmonary ventilation is regulated during inspiration and expiration when exercising
Chemoreceptors detect an increase in CO_2 -> inspiratory centre -> respiratory centre (medulla oblongata):
•(through phrenic nerve) -> diaphragm and external intercostals -> increased breathing rate
•-> exploratory centre -> stretch receptors - prevent over-inflation of lungs by sending impulses to expiratory centre
•(through intercostal nerve) -> abs and internal intercostals -> increase expiration
Define cilia
Microscopic hairs that move mucus up + away from lungs
Define COPD
(Chronic Obstructive Pulmonary Disease)
Lung condition as a result of long term lung damage
Explain the effect that smoking can have on the respiratory system
•irritation of trachea/bronchi -> swelling/narrowing of airways -> decrease lung function/breathlessness
•Damages cells lining trachea/bronchi -> mucus sits in the lungs = smokers cough
•damage alveolar walls (breaks them down) = larger spaces in alveoli than usual -> reduced gas exchange efficiency
•carbon monoxide combines with haemoglobin in BBC’s leaving less room for oxygen -> reduces oxygen carrying capacity
•tar in cigarettes - build up in airways = inhibits gas exchange
Explain the impact of this (smoking) for a marathon runner on performance
-> decrease oxygen delivered to working muscles
-> decrease aerobic respiration can occur -> build up of lactic acid earlier
-> run not as fast for as long
Identify + describe the characteristics of each muscle fibre type
•Slow oxidative (Slow twitch/type I)
•Fast oxidative glycolytic (type IIa) - fast twitch
•Fast glycolytic (type IIb) - fast twitch
Slow twitch muscle fibres - slower contraction, lower intensity exercise (long distance running), aerobically energy produced - use oxygen more effectively
Fast twitch fibres - faster contraction, generate greater force of contraction, fatigue quickly, used for short, intense bursts of effort, produce energy anaerobically - allow to use oxygen more effectively
type lla: greater resistance to fatigue, suited for longer duration anaerobic events - longer burst of energy needed
type IIb: fatigue quicker, used for highly explosive events - quick, short bursts of energy required
Apply the recruitment of muscle fibres to a sporting activity
Type I - long distance running, triathlon, long distance swimming
Type IIa - 400m/800m
Type IIb - shot, discus, long jump, 100m
Explain why a muscle fibre type is required for a particular activity (type I)
Type I - suited to long distance running
-> slow contraction speed - performer work at lower intensity
-> high mitochondria density - increase mitochondria - produce increase energy to allow exercise for longer
Repeat for other types
Explain the effect that training can have on muscle fibre type
•born with the number of muscle fibre types in your body -> genetically
•training -> cannot increase number of fibre type -> increase strength -> hypertrophy
Describe a motor unit
•consists of a motor neurone and it’s muscle fibres
•muscle fibres grouped into motor units
•only 1 type of muscle fibre found in 1 particular motor unit
Explain how a motor unit is recruited
•motor neurone sends impulses to stimulate the muscle fibres
•all or none of the fibres contract
•decided by ‘the threshold’ - a minimum amount of stimulation is required to start a contraction
•if impulses are equal or more than threshold all will contract
•if impulses less than threshold, no muscle action
Explain how we can vary the strength of a contraction
-number/type of motor units recruited
-size of motor units recruited
-frequency of impulses sent to muscle fibres -> wave summation
•increased frequency of stimuli, increased tension developed by muscle
•stimuli = impulses sent by the motor neurone
•increased frequency of stimuli = increased force of contraction
•increased frequency of stimuli to motor unit(s)
•repeated stimuli where fibres have no time to relax
•each time impulse teaches motor unit = release calcium
•increased tension in muscle = forceful, sustained contraction -> tetanic contraction
Apply the theory of wave summation to a sporting example
-> triple jump/lay up in basket ball
•wave summation would allow the triple jumper to produce a more powerful contraction
•muscle fibres are re-stimulated before they relax
•therefore the triple jumper will be able to apply greater force to the ground during hop and skip, taking more momentum into the jump = a further distance travelled through the air
Describe spatial summation
•recruitment of additional + bigger motor units within a muscle to develop more force
•frequency of impulses can also be staggered around motor units at slightly different times to contribute to a large sustained contraction
Explain spatial summation using a sporting example
Basketball - will use lots of large, fast twitch motor units in her quadriceps muscles to try to achieve as much height as possible to jump for the rebound
Describe PNF (proprioceptive neuromuscular facilitation)
-advanced stretching technique
-CRAC technique (contract - relax - antagonist - contract)
Describe the regulatory mechanisms for PNF
-muscle action controlled in PNF for movement to be effective. Achieved through proprioceptors
-muscle spindles + Golgi tendon organs -> lie in between skeletal muscle fibres - detect how far + fast muscle stretched
Muscle spindles: sends impulses to CNS -> CNS sends impulses back to muscle telling it to contract - triggers stretch reflex -> causes muscle to contract prevent overstretching - reduce risk of injury. Aim of PNF - override stretch reflex
Golgi tendon organs:
-found between muscle fibre + tendon
-detect levels of tension in muscle - signal info about load/force being applied to muscle
-when the isometric contraction occurs in PNF: causes tension in muscle, Golgi tendon organs sends signal to CNS, overrides signals sent by muscle spindles, delays stretch reflex
-allows antagonist muscle to relax
-autogenic inhibition: sudden relaxation of muscle in response to muscle tension by Golgi tendon organs
-leg stretches further
-greater range movement than initial stretch
Describe the CRAC technique in PNF stretching
1) individual performs passive stretch + extends leg till tension felt
•this stretch is detected by the muscle spindles
•if the muscle is stretching too far, a stretch reflex should occur
2) individually isometrically contracts muscle for 10 secs by pushing leg against partner who supplies enough resistance to hold leg stationary
3) antagonist muscle relax due to Golgi tendon organs - when partner pushes leg back, it stretches further
Apply PNF to different sports
Training method
Trampolining - increase flexibility - perform more difficult moves
Sprinting - increase stride length - increase speed
Games player - injury prevention
Name the bones
Cranium
Mandible
Clavicle
Sternum
Humerus
Radius
Ulna
Carpals
Metacarpals
Phalanges
Ribs
Pelvis
Ischium
Femur
Patella
Fibula
Tibia
Talus
Tarsals
Metatarsals
Cervical vertebrae
Scapula
Thoracic vertebrae
Lumbar vertebrae
Sacrum
Coccyx
Name the muscles
Anterior deltoid
Middle deltoid
Pectorals
Biceps brachii
Abdominals
Iliopsoas
Quadriceps
Tibialis anterior
Trapezius
Posterior deltoid
Rotator cuffs
Triceps brachii
Latisimus dorsi
Gluteus medius
Gluteus maximus
Adductor Magnus
Gastrocnemius
Define isotonic contraction
When a muscle contracts to create movement
Define concentric (isotonic contraction)
When a muscle shortens under tension
Define eccentric (isotonic contraction)
When a muscle lengthens under tension or performs negative work + acts like a brake
Define isometric contraction
When a muscle is under tension but there is no visible movement
Define flexion
Decreasing the angle between the bones of a joint
Define extension
Increasing the angle between the bones of a joint
Define hyper-extension
Increasing the angle beyond 180 degrees between the bones of a joint
Define plantar-flexion
Pointing the toes/pushing up on to your toes
Define dorsi-flexion
Pulling the toes up to the shin
Define abduction
Movement away from the midline of the body
Define adduction
Movement towards the midline of the body
Define horizontal abduction
Movement of limbs backwards across the body to shoulder abduction
Define horizontal adduction
Movement of limbs forward across the body at 90 degrees to shoulder abduction
Planes + axis
Sagittal plane -> transverse axis = forwards + backwards, up + down
Frontal plane -> sagittal axis = sideways
Transverse plane -> longitudinal axis = rotational
