B7.2 TRANSPORT Flashcards
What is the role of the heart in circulatory system?
To pump blood around the body.
What prevents blood flowing the wrong way round through the circulatory system?
Valves in the heart and veins.
Explain what is meant by a double circulatory system.
Blood passes twice through the heart for every once around the body –there are effectively two separate circulations of blood from the heart.
Name the four chambers of the mammalian heart.
Left atrium
Right atrium
Left ventricle
Right ventricle
Distinguish between arteries and veins.
Arteries carry blood away from the heart
Veins carry blood towards the heart
Starting in vena cava, list the chambers and blood vessels in the order that blood passes through them until it reaches the aorta.
Vena cava, right atrium, right ventricle, pulmonary artery, pulmonary vein, left atrium left ventricle, aorta.
Explain why resting heart rate in an adult is given as a range of values and not a single value.
Resting heart rate varies widely due to many factors, including age, health and fitness, so a single value for the average is too limited.
Explain the effect of activity on heart rate.
Heart rate increases with exercise
so the blood can circulate faster around the body, delivering oxygen and glucose to muscle cells
for the increased rate of respiration
to generate the energy needed for contraction.
It also removes waste carbon dioxide from muscle tissue more rapidly
to prevent it building up and effecting cells.
Explain why the heart needs its own blood supply.
To supply the oxygen and glucose needed for the heart muscle cells to respire and to remove waste carbon dioxide.
Identify four possible risk factors for coronary heart disease.
Smoking, stress, diet containing a lot of saturated fat, genetic factor.
Explain how a person can reduce their risk of coronary heart disease.
Eat a diet that relatively low in saturated fat
Don’t smoke
Try to control stress and the effects that it has on behavior.
