3.2.2. White blood cells play a particularly important role in …
a. Carrying oxygen
b. Blood clotting
c. Haemoglobin transport
d. Carrying carbon dioxide
e. Fighting infections
3.2.1. A two-cycle circulatory system has an advantage over a one-cycle system in that …
a. Blood can be directed to target tissue more specifically
b. The arterial part of the systemic system is at high pressure
c. The arterial part of the pulmonary system is at high pressure
d. The direction of blood flow can be reversed
e. Oxygen can be delivered directly to the tissue from the tracheal system