Which of the following is true about blood pressure?
a. it is not affected by atherosclerosis.
b. it falls when the heart contracts.
c. diastolic pressure is higher than systolic pressure.
d. artery walls to maintain pressure, even between heart beats.?

How do you know that the plant cells in these two images have different jobs, or functions? a. because all plant cells serve different functions b. because they are two different colors c. because their dna are different d. because their structures are different