(a)[5]
Complete the statements about the circulatory system. The heart [BLANK] blood through the body. Blood leaves the heart in vessels named [BLANK]. Blood returns to the heart in vessels named [BLANK]. Nutrients reach cells through vessels called [BLANK]. The presence of [BLANK] keeps blood flowing in one direction.
(b(i))[1]
State the number of heart beats in $2.8$ seconds during exercise.
(b(ii))[1]
Calculate the percentage increase in heart beats from rest to exercise.
(c)[3]
Describe other methods of lowering a person’s risk of developing coronary heart disease.
(d)[1]
State what causes the heart sounds heard through the stethoscope.