Humans have a double circulatory system. There is a low pressure circulation and a high pressure circulation. Explain how the structure of the heart enables it to pump blood into circulations at different pressures.

The human heart is a pump. It pumps blood around the body at different speeds and at different pressures according go the body's needs. It can do this because the wall of the heart is made from cardiac muscle. Blood is moved through the heart by a series of contractions and relaxations of cardiac muscle in the walls of the four chambers.

evidence and logical support is essential for a scientist to do in order to maintain credibility. this is because no one can believe without any logic and without any evidence.hence a scientist can maintain credibility by proving himself and by answering logically so experiments prove very beneficial. logical hypothesis give conclusion which is acceptable. therefore, there are two main factors to maintain credibility by a scientist is evidence and logical support.