Why does the heart start pumping blood to all the cells so early in pig development

Moving down the ramp from 6 meters to

Cancer cells spread to other parts of the body by entering the bloodstream. which of the following organs could prevent a cancer cell in the bloodstream from spreading, and why? a. the spleen, because it releases lymphocytes into the blood b. the peyer's patches, because they release lymphocytes into the blood c. the lymph nodes, because they release lymph into the blood d. the thymus, because it releases lymph into the blood

What is the ratio of carbon hydrogen and oxygen in a carbohydrate?