Question

Give a brief account of the components responsible for the transport of substances in the human body.

Answer 1

The system of tubes with a pump and valves which ensures the one-way blood flow is the human transport system and delivers oxygen and other essential nutrients with other substances to the body cells and takes the waste products from them.

Complete answer:
The transport system constitutes the components which are the heart, blood, and the blood vessels. The heart is a muscular organ that is almost the size of a fist and pumps blood throughout the blood vessels of the circulatory system which carries the oxygen and nutrients to the body and carries the metabolic waste such as the carbon dioxide to the lungs. It is located between the lungs in the middle compartment of the chest and is divided into four chambers which are the right atrium, the right ventricle, the left atrium, and the left ventricle. Blood is a body fluid that delivers the necessary substances and is composed of blood cells that are suspended in the blood plasma that constitutes the 55% of the blood fluid and is mostly water containing proteins, minerals, glucose, hormones, carbon dioxide, and blood cells. The components of the circulatory system which transport blood throughout the body is the blood vessel which takes waste and carbon dioxide away from the tissues and delivers the nutrients and oxygen which are needed to sustain life and all body tissue rely on their functionality.

Additional information:
The fluid which fills the arterial system is known as effective arterial blood volume. Arteries are responsible for the transportation of nutrients and oxygen to deliver to all parts of the cell. It also helps to remove carbon dioxide and waste products. It helps in maintaining the optimum blood pH and circulation of protein. The outermost layer of an artery which is known as the tunica externa consists of collagen fibers and elastic tissues. Its boundary is not well defined and considered when it meets the connective tissue. The tunica media is the middle laya which is composed of smooth muscle, collagen fibers, and elastic tissues. The innermost layer is involved in direct contact with the flow of blood and is known as tunica intima. Veins are less muscular and are present closer to the skin. It prevents the backflow of blood by valves. They are known as capacitance vessels due to the most amount of blood volume which is present in them around $60\%$.

Note:
The human circulatory system is spread along 66000 miles which is equal to more than two and half times the circumference of the earth. During the life of a 75-year-old t, the heart beats about 2.5 billion times and expels two ounces of blood with each beat.