Applied Anatomy and Physiology Flashcards
Myogenic
Originating in muscle tissue.
Sinoatrial Node (SAN)
A small mass of cardiac muscle found in the wall of the right atrium that generates the heartbeat. It is more commonly known as the pacemaker.
Atrioventricular Node (AVN)
Relays the impulse between the upper and lower sections of the heart.
Medulla Oblongata
The most important part of the brain as it regulates processes that keep us alive.
Ejection Fraction
Percentage of blood pumped out by the left ventricle per beat.
Venous Return
The return of blood to the right side of the heart via the vena cava.
Cardiac Hypertrophy
When the heart becomes bigger and stronger due to a thickening of the muscular wall.
Bradycardia
When there is a decreases in resting heart rate to below 60 beats per minute.
Atherosclerosis
When arteries harden and narrow and become clogged up by fatty deposits.
Systolic
When the ventricles are contracting.
Diastolic
When the ventricles are relaxing.
Myoglobin
An iron-containing muscle pigment in slow twitch muscle fibres which has a higher affinity for oxygen than haemoglobin. It stores the oxygen in the muscle fibres which can be used quickly when exercise begins.
Mitochondria
Site at which respiration and energy production occur.
Bohr Shift
When an increase in blood carbon dioxide and a decrease in blood pH results in a reduction of the affinity of haemoglobin for oxygen.
Vascular Shunt Mechanism
The redistribution of cardiac output.
Vasodilation
The widening of the blood vessels to increase blood flow into the cappilaries.
Vasoconstriction
The narrowing of the blood vessels to reduce blood flow into the capillaries.
Arterio-Venous Difference (A-VO2 Diff)
The difference between the oxygen content of the arterial blood arriving at the muscles and the venous blood leaving the muscles.
Tidal Volume
The volume of air inspired or expired per breath.
Minute Ventilation
The volume of air inspired or expired per minute.
Inspiratory Reserve Volume (IRV)
The volume of air that can be forcibly inspired after a normal breath.
Expiratory Reserve Volume (ERV)
The volume of air that can be forcibly expired after a normal breath.
Residual Volume
The amount of air that remains in the lungs after maximal expiration.
Gaseous Exchange
The movement of oxygen from the air into the blood, and carbon dioxide from the blood into the air.
Partial Pressure
The pressure exerted by an individual gas when it exists within a mixture of gases.
Diffusion
The movement of gas molecules from an area of high concentration or partial pressure to an area of low concentration or partial pressure.
Concentration/Diffusion Gradient
Explains how gases flow from an area of high concentration to an area of low concentration. The steeper this gradient, the faster diffusion occurs.
Pulmonary Ventilation
Breathing
Adrenaline
The hormone that increases breathing rate in preparation for exercise.
Motor Unit
A motor neurone and its muscle fibres.
All or None Law
Where a sequence of impulses has to be of sufficient intensity to stimulate all of the muscle fibres in a motor unit in order for them to contract. If not, none of them contract.
Wave Summation
Where there is a repeated nerve impulse with no time to relax, so a smooth, sustained contraction occurs rather than twitches.
Tetanic Contractions
A sustained powerful muscle contraction caused by a series of fast repeating stimuli.
Spatial Summation
When the strength of a contraction changes by altering the number and size of the muscle’s motor units.
CRAC
contract-relax-antagonist-contract
Muscle Spindles
Proprioceptors that detect how far and how fast a muscle is being stretched and produce the stretch reflex.
Autogenic Inhibition
Where there is a sudden relaxation of the muscle in response to high tension. The receptors involved in this process are Golgi tendon organs.
Articulating Bones
Bones that meet and move at the joint.
Abduction
Movement away from the midline of the body.
Adduction
Movement towards the midline of the body.
Isotonic Contraction
When a muscle contract to create movement.
Concentric Contraction
When a muscle shortens under tension.
Eccentric Contraction
When a muscle lengthens under tension.
Isometric Contraction
When a muscle can contract without actually lengthening or shortening and the result is that no movement occurs.
Adenosine Tri-Phosphate (ATP)
The only usable form of energy in the body.
Glycolysis
The breakdown of glucose into pyruvic acid.
Krebs Cycle
A series of cyclical chemical reaction that take place using oxygen in the matrix of the mitochondria.
Electron Transport Chain
This involves a series of chemical reactions in the mitochondria where hydrogen is oxidised to water and 34 molecules of ATP are produced.
Sarcoplasm
The fluid that surrounds the nucleus of a muscle fibre; the site where anaerobic respiration takes place.
Beta Oxidation
A process where fatty acids are broken down to generate acetyl-CoA, which enters the Krebs cycle.
Phosphocreatine (PC)
An energy-rich phosphate compound found in the sarcoplasm.
Anaerobic
A reaction that can occur without the presence of oxygen.
Energy Continuum
A term which describes which type of energy system is used for different types of physical activity and sport. The contribution of each system depends on the intensity ad duration of exercise.
Oxygen Consumption
The amount of oxygen we use to produce ATP.
Submaximal Oxygen Deficit
When there is not enough oxygen available at the start of exercise to provide all the energy (ATP) aerobically.
EPOC
The amount of oxygen consumed during recovery above that which would have been consumed at rest during the same time.
Fast Replenishment Stage
The restoration of ATP and phosphocreatine stores and the re-saturation of myoglobin with oxygen.
Cori Cycle
The process where lactic acid is transported in the blood to the liver where it is converted to blood glucose and glycogen.
Lactate Threshold
The point at which lactic acid rapidly accumulates in the blood.
OBLA
The point when lactate levels go above 4 millimoles per litre.
VO2 Max
The maximum amount of oxygen that can be utilised by the muscles per minute.
Buffering
A process which aids the removal of lactate and maintains acidity levels in the blood and muscle.
Direct Gas Analysis
Measures the concentration of oxygen that is inspired and the concentration of carbon dioxide that is expired.
Cycle Ergometer
A stationary bike that measures how much work is being performed.
Plyometrics
Repeated rapid stretching and contracting of muscles to increase muscle power.
