Question

Which of the following is correct? *

1 )The heart is made up of four chambers.
2)The heart works by contracting and relaxing its muscles.
3)The blood rich in carbon dioxide flows through the right side of the heart, while the blood rich in oxygen flows through the left side of the heart
4)All the above​
pls tell emergency....
pls

Answer 1

All of the above is the correct answer

Pls mark as brainlist