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Human Anatomy & Physiology: The Blood

What is Blood?

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Blood Lesson Transcript

Hi and welcome back to This is the lesson on blood. Blood has numerous functions not just circulating fluids. It is the transport of nutrients, sugars, proteins, lipids, vitamins, etc. Gases, oxygen, and CO2 are among them. Wastes are the ones that you will end up excreting either through your urine, your sweat, etc. Hormones the way that hormones actually get to organs and cause them to change something like the physiology is through blood.  Regulation of ph, ph has to do with acid vs. bases. You have a zone in which your ph in your body need to be maintained there. Regulation of ph, ph has to do with acid vs. bases.  You have a zone in which your ph in your body need to be maintained there. The approximate ph for the human bloodstream is 7.4 ever so slightly basic. If that goes down to below 7 that is enough to kill a person because of the ph kills logarithmic and you want to keep it in a very particular range. Your bloodstream has a lot to do with regulating that. Restriction of fluid loss during an injury. If you do have a cut, you are bleeding or hemorrhaging some are carried into your blood in able to stop that. Defense against pathogens and toxins. White blood cells or the parts of the blood that are primarily protecting you and killing off foreign invaders. Regulation of body temperature that is very important as well. Before I move on I want to show you what these are. This is your old average red blood cell. This is a platelet and this is a white blood cell. More often than not white blood cells or leukocytes are going to be much larger than red blood cells but we do have a heck of a lot more red blood cells. The ratio of red blood cells to white blood cells in the blood is approximately 1,000 to 1. That is why your blood is usually red because of the red blood cells. This is a micrograph. This is an actual image. It is not computer generated. If you take a blood sample from a person and centrifuge it, spin around really fast, you will get a separation of all the blood parts by density. Than densest parts specifically was called hematocrit. Hematocrit is the solid blood parts majority which is red blood cells. You are going to get that in certain parts of the body because those solid particles and cells are much more dense. The fluid portion of blood is going to stay on the top. When we look at all the portions let us start at the bottom.

Erythrocytes is the technical term for red blood cells. Erythro means red and cyte means cell. Approximately 45% of the average person’s blood is the red blood cells. The other part up next is the buffy coat. There is this white band that tends to be a coming together of all of your white blood cells and platelets which are just slightly less dense than you compacted red blood cells. Thrombocyte is the technical term for platelets. Leukocyte is the technical term for white blood cells. We will talk more about the functions of these later. Plasma is the yellow fluid. The particles dissolved in plasma would give you that yellow look. There are lots of particles dissolved in the plasma, the actual fluid of your blood. A lot of plasma most of it is water. You also have gases, oxygen, CO2, and nitrogen gas. There is a lot of them You are going to have nutrients, all those molecules that is meant to nourish your body. On the flip side of that, our waste, those waste products that are going to be eventually excreted. On top of all that you are going to have hormones. A lot of hormones get all the different the cells via the fluid of your blood and you also have dissolved blood proteins. Included in the nutrients are going to be amino acids and proteins that you are feeding your cells. Your cells need proteins to function to stay alive. These proteins they stick around the blood and they all have their own purposes. The majority of these blood proteins is 60% of them approximately is the albumins. Albumins are hanging around your blood to help maintain osmotic pressure. If you took biology osmosis has to do with the passive or means moving without energy that the passive natural movement of water to where there is less water by concentration. If you do not have as many albumins in your bloodstream as you do, there will be too much water flow. Think about this, having blood proteins in your blood helps keep water there. If there are a lot less then you actually would sometimes lose too much water out of your bloodstream. Albumins help maintain that osmotic pressure in your body. Next up globulins, there are 2 main kinds of globulins. The one that you have probably heard most about is antibodies. Antibodies is the type of globulin protein those are very specifically shaped molecules that are meant to attach and help the white blood cells attack foreign invaders. They will attach to bacteria and viruses to immobilize them and to mark them so they can get destroyed us they cannot harm you. Antibodies is one type of globulin. Another type of globulin is a transport proteins. There are certain substances in the bloodstream that are necessarily get along with water. It might be non polar particle that does not dissolve well in the plasma. Globulins that are the transport variety will sometimes be like a little shuttle or raft getting them through the blood stream. Certain hormones need to be attached to globulins. And finally the next major kind of blood protein is fibrinogen. Fibrinogen is what you made fiber and out of. Without fibrinogen you wouldn’t be able to make a blood clot. A blood clot is the way that you stop bleeding and it is very important. There are the components of plasma and the other blood components.

About Prof. Bryan Cardella

Blood Anatomy Physiology Educator

Professor Bryan Cardella combines Anatomy and Physiology to help you understand both the structures of the human body and how they work with each other. This course is perfect for both high school and college students, and is more in-depth than standard introductory courses. Every major organ system is covered, with tons of pictures, diagrams, and explanations. Professor Cardella brings both extensive knowledge and engaging delivery with his 10+ years teaching life sciences and stand-up comedy experience.

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