Topic 2 Flashcards
2.1
Structure and function of the ventilatory system
Components of the ventilatory system
Mouth Nose Pharynx Larynx Trachea Bronchi Bronchioles Lungs Alveoli
Functions of the conducting airways
Low resistance pathway for airflow
Defence against harmful substances or chemicals that can be inhaled
Warms and moistens air
Pulmonary ventilation
Pulmonary ventilation is the inflow and outflow of air into the lungs
Total lung capacity
The volume of air in the lungs after maximum inhalation
Vital capacity
The maximum volume of air that can be exhaled after a maximum inhalation
Tidal volume
The volume of air breathed in and out in any one breath
Expiratory reserve volume
Volume of air in excess of tidal volume that can be exhaled forcibly
Inspiratory reserve volume
The volume of air a person can inhale in excess of their tidal volume
Residual volume
Volume of air still contained in the lungs after a maximal exhalation
Explain the mechanics of ventilation in the human lungs
The diaphragm contracts and the intercostal muscles allow the ribs to expand allowing the lungs to contain more air.
Boyle’s law states that an increase in pressure leads to a decrease in volume and an increase in volume leads to a decrease in pressure.
Describe nervous and chemical control of ventilation during exercise
Ventilation increases as a direct result of increases in blood acidity levels (low pH) due to increased carbon dioxide content in the blood detected by the respiratory centre. This results in an increase in the rate and depth of inhalation.
Neutral control of ventilation includes lung strech receptors, muscle proprioreceptors and chemoreceptors.
The role of hydrogen ions and reference to partial pressure of oxygen are not required.
Outline the role of hemoglobin on blood
98.5% of oxygen in the blood is transported by hemoglobin whithin red blood cells
Explain the process of gaseous exchange at the alveoli
The delivery of oxygen from the lungs to the bloodstream, and the elimination of carbon dioxide from the bloodstream to the lungs. These processes occur through diffusion.
2.2
Structure and function of the cardiovascular system
Composition of blood
Composed of:
Plasma (55%)
Red blood cells (45%) - Erythrocytes
White blood cells and platelets (<1%) - Leucocytes
Functions of erythrocytes, leucocytes and platelets
Erythrocytes - Contain haemoglobin which is responsible for transporting oxygen
Leucocytes - Protect the body from infection an diseases
Platelets - Assists the process of repair following injury (blood clotting)
Anatomy of the heart - Chambers
Right atrium
Left atrium
Right ventricle
Left ventricle
(On diagrams left is right and right is left)
Anatomy of the heart - Valves
Going from left to right on diagrams (right to left in real life)
Tricuspid
Pulmonary
Aortic
Bicuspid
Anatomy of the heart - Blood vessels
Inferior vena cava
Pulmonary artery
Pulmonary vein
Aorta
Pulmonary and systemic circulation
Pulmonary circulation - The flow of deoxygenated blood from the right ventricle, through the pulmonary artery, to the lungs where it becomes oxygenated and then travels through the pulmonary veins back to the heart, ready to be pumped to the rest of the body.
Systemic circulation - The flow of oxygenated blood from the left ventricle, through the aorta to the rest of the body.
Intrinsic and extrinsic regulation of heart rate
The heart has its own pacemaker, but heart rate is also influenced by sympathetic and parasympathetic branches of the autonomic nervous system and by adrenaline.
The sequence of excitation of the heart muscle
The electrical impulse is generated at the sinoatrial node (SA node) and travels across the atria to the atrioventricular node (AV node) and then to the ventricles, which allows the heart to beat
Describe the relationship between heart rate (HR), cardiac output (CO) and stroke volume (SV) at rest and during exercise
Cardiac output = Stroke volume x Heart rate
At rest, CO, SV and HR remain constant
During exercise HR and SV increase, therefore CO is larger
Analyse cardiac output, stroke volume and heart rate for different populations at rest and during exercise
Men vs Women
Men have a lower resting HR but they are equal at max
Men have a higher SV compared to women
Men have a higher VO2 max
Women peak is late teens, men peak is early 20s
Young vs Old
Young people have a higher HR than older people
Young people therefore have a higher SV
Dependant on training
Trained vs Untrained
Trained people have a lower resting HR but at max are equal
Trained people have a higher SV
Trained people therefore have a higher VO2 max
Explain cardiovasuclar drift
Cardiovascular drift is the increase in heart rate and decrease in stroke volume during exercise. The stroke volume decreases as when a person sweats, their blood viscosity changes and becomes thicker which makes it harder to pump.
Systolic and diastolic blood pressure
Systolic blood pressure - the force excerted by blood on arterial walls during ventricular contraction
Diastolic blood pressure - the force excerted by blood on arterial walls during ventricular relaxation
Systolic and diastolic blood pressure pressure during static and dynamic exercise
At rest, systolic pressure and diastolic blood pressure remains constant
During static exercise, systolic blood pressure increases and diastolic blood pressure increases
During dynamic exercise, systolic blood pressure increases slowly and diastolic blood pressure remains constant
Compare the distribution of blood at rest and the distribution of blood during exercise
At rest, blood is distributed equally throughout the body as all muscles are working more or less the same
During exercise, blood is distributed to the muscles that are doing the most work and therefore need the most oxygen
Describe the cardiovascular adaptations resulting from endurance exercise training
As the left ventricular volume increases, the stroke volume also increases and the heart rate decreases.
Capilarisation is increased and arterio-venous oxygen difference is increased.
Explain maximal oxygen consumption
Maximal oxygen consumption/VO2 max is the maximum amount of oxygen that a person breathes in whilst exercising at their maximum level.
Discuss the variability of maximal oxygen consumption in males vs females, old vs young, trained vs untrained
Older people generally have a higher maximal oxygen consumption compared to younger people, but it is dependant on how active and fit they are
Males tend to have a higher VO2 max compared to females as their stroke volume is on average higher at max.
Trained people have a higher VO2 max compared to untrained people as they have a higher max stroke volume
Discuss the variability of maximal oxygen consumption with different types of exercise
Running vs arm ergometry
Running requires a higher maximal oxygen consumption when compared to arm ergometry as it involves a greater muscle mass. This means more oxygen is required to allow the muscles to function. It is also important to consider that previous training in each exercise will change the maximal oxygen consumption required.
