Cardiovascular system
An organ system that distributes the blood to deliver nutrients and remove waste.
Blood pressure – force exerted by blood against a unit area of the blood vessel walls
(mmHg); differences in blood pressure between different areas of the circulation provide the
driving force for blood circulation.
Blood pressure is always a major risk factor in health.
Cardiac output – (ml/min)
Stroke volume (ml/beat)
Heart rate (beats/min)
Cardiac output – amount of blood pumped out of a ventricle in one minute.
Roles of cardiovascular system,
Transport – e.g. oxygen, cardio dioxide, nutrients. Close enough so that diffusion can take
place.
Communication – hormones transported (e.g. adrenaline, insulin)
Homeostasis: temperature, pH and blood pressure.
Blood vessles
Arteries – oxygenated blood away from the heart
Veins – deoxygenated blood back to the heart
Capillaries – join the two. Where diffusion takes place.
Blood pressure:
Normally systemic arterial pressure of large vessels of the body (mmHg)
Aorta
Brachial artery
Radial artery
Femoral artery
Tibial artery
Systolic (contraction) BP. Middle ventricular contraction -120mmHg
Diastolic (relaxation) BP. Ventricular diastole. Semilunar valves closed -80mmHg
Mean arterial BP – ‘average’ BP produced by heart
- 93 mmHg
- Map = diastolic BP + 1/3 pulse pressure
Equation: blood pressure = cardiac output x total peripheral resistance
Maintain flow and pressure to areas that need it
High blood pressure (Hypertension)
Chronic hypertension – obese and ederley – leads to heart disease, renal failure, stroke
An organ system that distributes the blood to deliver nutrients and remove waste.
Blood pressure – force exerted by blood against a unit area of the blood vessel walls
(mmHg); differences in blood pressure between different areas of the circulation provide the
driving force for blood circulation.
Blood pressure is always a major risk factor in health.
Cardiac output – (ml/min)
Stroke volume (ml/beat)
Heart rate (beats/min)
Cardiac output – amount of blood pumped out of a ventricle in one minute.
Roles of cardiovascular system,
Transport – e.g. oxygen, cardio dioxide, nutrients. Close enough so that diffusion can take
place.
Communication – hormones transported (e.g. adrenaline, insulin)
Homeostasis: temperature, pH and blood pressure.
Blood vessles
Arteries – oxygenated blood away from the heart
Veins – deoxygenated blood back to the heart
Capillaries – join the two. Where diffusion takes place.
Blood pressure:
Normally systemic arterial pressure of large vessels of the body (mmHg)
Aorta
Brachial artery
Radial artery
Femoral artery
Tibial artery
Systolic (contraction) BP. Middle ventricular contraction -120mmHg
Diastolic (relaxation) BP. Ventricular diastole. Semilunar valves closed -80mmHg
Mean arterial BP – ‘average’ BP produced by heart
- 93 mmHg
- Map = diastolic BP + 1/3 pulse pressure
Equation: blood pressure = cardiac output x total peripheral resistance
Maintain flow and pressure to areas that need it
High blood pressure (Hypertension)
Chronic hypertension – obese and ederley – leads to heart disease, renal failure, stroke
