(Q).
Q: What is the sequence of elementary steps that together comprise an entire chemical reaction called? Choices: - reaction circle - mechanical mechanism - basic reaction - reaction mechanism A:
(A).
reaction mechanism

(Q).
Q: Macrophages, which can swallow and destroy old and dying cells, bacteria, or viruses, are large types of what cells? Choices: - red blood cells - white brain cells - dendritic cells - white blood cells A:
(A).
white blood cells

(Q).
Q: What is the hollow sac like organ that stores urine until it is excreted? Choices: - kidney - ureter - tumor - bladder A:
(A).
bladder