Why didn’t the greatest heart anatomist in history, Leonardo da Vinci, discover this simple technique that would prove that it was a pump?

He found that the heart had four chambers and it connected the pulse in the wrist with the contraction of the left ventricle. He worked out that currents in the blood flow, created in the main aorta artery, help heart valves to close. And he suggested that arteries create a health risk if they fur up over a lifetime.

Explanation:

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.

the answers are as following:

1. c. double helix, nucleosome, coil, supercoil, chromosome

2. b. g2 phase, preparation for mitosis

3. d. interphase consists of the g1, s, and g2 phases

4. c. metaphase

5. a. chromosomes are duplicated before cell division so that each new daughter cell has a complete set