Arteries must be thicker than veins to be able to withstand the high pressure the heart exerts as it pumps blood into them. As blood travels
through the body, this pressure decreases. Blood pressure is the lowest in the veins as the blood heads back to the heart.
Based on blood pressure differences between arteries and veins, which of these must be true?
OA Blood flow tends to be faster in arteries than in veins.
O B. Blood pH tends to be higher in veins than in arteries.
OC. Blood flow tends to be faster in veins than in arteries.
OD. Blood viscosity tends to be higher in arteries than in veins.

A Blood flow tends to be faster in arteries than in veins.

Explanation:

Veins and arteries are both blood vessels i.e. conducts blood in the circulatory system. As rightly said in the question, the walls of the arteries are thicker and stronger than that of veins in order to be able to withstand the high pressure of blood that flows into it from the heart. The veins, on the other hand, has a lower blood pressure since blood flows back into the heart.

Based on this fact that blood flows forcefully i.e. high pressure, out of the heart into the arteries, blood will flow faster in the arteries i.e. with high speed which is responsible for the high pressure that the blood exerts on its wall.

Option A

Explanation:

Blood flow which is characterized by its velocity tends to be faster in arteries than in veins and inversely varies as its cross-sectional area. Blood flow is faster in the arteries as it carries blood away from the heart at  high blood pressure rate and this continues if the cardiac output is continually compensated for.

lunar landing mission. apollo 11 was the first manned mission to land on the moon. the first steps by humans on another planetary body were taken by neil armstrong and buzz aldrin on july 20, 1969. the astronauts also returned to earth the first samples from another planetary body.

explanation: