What is the circulatory system?
The circulatory system is a bodily system that circulates blood throughout the body; the system consists of the heart, blood vessels, blood, lymphatic vessels and glands. The purpose of the circulatory system is to move blood to a region of the body where it can be oxygenated and where waste can be disposed of. The circulatory system also serves to bring newly oxygenated blood to tissues of the body (e.g; muscles and organs). Once the blood has diffused through the alveoli, and the co2 has moved across the capillaries to exit the body, the blood will circulate throughout the body to remove waste in organs such as the liver, and kidneys.
Furthermore this process is vital for the life of cells, tissue and organisms, without it organisms such as humans would have no means of transporting vital substances, and nutrients that are essential for human life. An example of when the circulatory system is important is when running. When running your body will need a higher demand of oxygen, this is because your muscles will be working harder causing them to need a larger supply of oxygen. When your body doesn’t have large enough supply oxygen it begins to make a waste product call lactic acid, this by-product of decreased oxygen intake can cause your liver to become fatty which in turn will hinder your body’s natural processes and can lead to death.
What organisms don’t have a circulatory system?
Organisms such as invertebrates do not have a circulatory system, the reason being that their cells are small enough and close enough for them to gain oxygen and nutrients through they’re environment. Another reason that they don’t have a circulatory system is that unlike humans that are far too big to diffuse waste (co2) through their skin, vertebrates are able to diffuse waste products such as co2 through their cells due to them having a small body composition.
What is a closed circulatory system and what organisms have it?
A closed circulatory system is a circulatory system in which blood travels through the body in closed vessels (i.e. veins, arteries and capillaries). Closed circulatory systems blood is restricted to vessels; this means that the blood cannot freely flow throughout the body, whereas an open circulatory system allows the blood to freely