Instead, they have an open circulatory system, with body cavities full of hemolymph (the insect version of blood). With our other experiments we have learned that cockroaches have a similar nervous system to humans, but does this hold true with the circulatory system? Unfortunately, for those of us who like to bask in the magnificence of cross-species similarities in nature, the cockroach, like all insects, does not have a circulatory system like ours. Plasma makes up for a little more than 50% of your blood, making it the most plentiful component of your blood.
It is mostly water, but also consists of proteins, sugars, electrolytes, and other essentials. Plasma is the fluid that allows for the movement of cells throughout your circulatory system. Then, once the damage has been healed up by the body, the clot is absorbed back into the body. When you hemorrhage, they begin sticking together at the site of the damage until they have created a physical blockade, or a plug, preventing further blood from escaping. Platelets are tiny cells, about one fifth the diameter of a red blood cell. Platelets are responsible for our blood's ability to clot. White blood cells can "eat" pathogens (they engulf the pathogen and then use enzymes to break it down), release antibodies to destroy them, or release antitoxins to combat the effects of certain pathogens. With different specializations comes different approaches to dispatching the pathogens. There are a variety of types of white blood cells in our body which specialize in targeting different kinds of pathogens. They are our second line of defense against illness (the first being the external barriers like skin), destroying "pathogens" (disease causing material) that can damage us or make us sick. White blood cells are our body's defense system. Oxygen is important to us because it allows our cells to metabolize (transform) nutrients into energy that can fuel our body's movement and growth. Red blood cells are responsible for keeping us alive! Our heart pumps our blood, our lungs oxygenate the red blood cells, and the red blood cells transfer the oxygen to cell tissues through a process called cellular respiration. Now, to the blood! Remember, our blood is made up of four components: red and white blood cells, platelets, and plasma. The cardiovascular system is just a more focused term, referring primarily to the heart (cardio) and blood vessels (vascular). You may also hear the circulatory system referred to as the cardiovascular system. An important ability of our body's blood is its ability to clot, or to create a blockage that stops the blood from hemorrhaging, giving the body time to regenerate cells and heal the injury. When you suffer from broken blood vessels, such as a cut or scrape, this is called a hemorrhage. This means that our blood isn't just sloshing around inside of us, instead, our heart is forcefully pumping blood throughout our blood vessels. As its name suggests, a "closed" system means that all of our blood flows through arteries, veins, and capillaries. Humans have a closed circulatory system which delivers oxygen, nutrients, hormones, and other essentials throughout our body.
Before getting into the blood science, however, it is helpful to learn a bit about circulatory systems! Then, let's take this opportunity to learn a bit about the Cockroach too! Have you ever heard of something being referred to as a "life blood?" Well that's because blood is responsible for keeping nearly all of our body's cells alive and growing! Our blood is made up of four main components: white blood cells, red blood cells, platelets, and plasma - each of which serve specific purposes.