A&P - Subject Specific Vocabulary Flashcards
Define Anticipatory Rise
An increase in heart rate prior to exercise, due to the release of adrenalin.
Define AVO2-Diff
The difference in the oxygen content of the blood between the arterial blood and the venous
blood.
Define Systolic Blood Pressure
- Systolic blood pressure: Blood pressure while the heart is contracting.
Define diastolic blood pressure
- Diastolic blood pressure: Blood pressure while the heart is relaxing.
Define Bohr Shift
The Bohr shift is when an oxyhaemoglobin dissociation curve moves to the right during
exercise. An oxyhaemoglobin dissociation curve correlates the oxygen saturation of
haemoglobin across a range of oxygen pressures
Define Bradycardia
A reduction in resting heart rate below 60 beats per minute.
Define sino-atrial node
the heart’s pacemaker, which sends an impulse through the atria
causing them to contract.
Define cardiac conduction system
A group of specialised cardiac muscle cells in the walls of the heart that send signals to the heart
muscle, causing it to contract. The main components of the cardiac conduction system are
Define cardiac hypertrophy
Increase in thickness of the muscular heart wall, especially around the left ventricle
Define cardiac output
Cardiac output is the amount of blood which leaves the left ventricle per minute. It is calculated
by multiplying heart rate and stroke volume
Define heart rate
Heart rate is the number of times the heart contracts per minute
Define stroke volume
Stroke volume is the amount of blood which leaves the left ventricle per contraction.
Define cardiovascular drift
A reduction in stroke volume when exercising in warm conditions for longer than 10 minutes.
Results in an increase in heart rate to maintain cardiac output.
Occurs due to sweating which reduces blood volume and increases viscosity. This decreases
venous return which, in line with Starling’s law, decreases stroke volume.
Define haemoglobin
Found in red blood cells. Haemoglobin combines with oxygen to form oxyhaemoglobin,
transporting it around the body.
Define myoglobin
Found in muscle cells, myoglobin stores and transports oxygen. It has a higher affinity for
oxygen than haemoglobin, so it aids transport into muscle cells.
Define vasodilation
Vasodilation: Precapillary sphincters will relax, widening the internal diameter of blood
vessels. During exercise this will happen in the vessels leading to working muscles allowing
more oxygen and nutrient rich blood to reach them.
Define vasoconstriction
Precapillary sphincters will contract, decreasing the internal diameter of
blood vessels. During exercise this will happen in the vessels leading to non-working
muscles and non-essential organs eg digestive system. This allows more blood to be
available for the working muscles.
Define venous return
Increased venous return will result in a higher stroke volume. The is due to the cardiac muscle
being stretched, resulting in a stronger force of contraction and greater ejection fraction.
Define ischaemic strokes
occur when a blood clot stops the supply of blood reaching the brain.
These are the most common type.
Define Haemorrhagic strokes
- Haemorrhagic strokes are the result of a weakened blood vessel to the brain bursting.
Define valves
- Valves: Found in veins that prevent the backflow of blood.
Define skeletal muscle pumps
Skeletal muscle pump: Working muscles contract and compress veins to push blood back
towards the heart
Define respiratory pumps
Respiratory pump: Increased respiration/changes in pressure in the thorax compress
veins to push blood back towards the heart.
Define diffusion
The movement of gases from an area of high partial pressure to an area of low partial pressure.
Define expiratory reserve volume
The volume of air which could be forcibly expired in addition to tidal volume.
Define inspiratory reserve volume
The volume of air which could be forcibly inspired in addition to tidal volume.
Define minute ventilation
Volume of air inspired or expired per minute. Breathing rate x tidal volume.
Define partial pressure
The pressure exerted by an individual gas in a mixture of gases.