Viruses are different from living things in a way that they cannot live outside their host cells for a long time .and become crystalline.
D) smallest particle with all the properties of an element
Correct answer is (D. Once created in bone marrow, they circulate for our lifetime)
Ventricular systole is when the ventricles of the heart as the result of electrical activity which helps to pump blood. During ventricular systole oxygenated blood is pumped from the left ventricle through the aortic valve and aorta. Simultaneously deoxygenated blood is pumped from the right ventricle through the pulmonic valve and pulmonary artery to the lungs. Using this explanation blood enters the aorta and pulmonary artery during ventricular systole. <span />
I think the answer is d ... hope this helps
