The Blood You Need to Know: Understanding Blood Types, Transfusions, and Why Regular Donations Matter

From Plasma to Platelets: A Comprehensive Guide to the Components of Human Blood

Transfusions of blood or its components may be necessary in cases of injury, illness, or surgery, and regular blood donations are important for maintaining an adequate supply for medical use. Blood is consists of four main components: red blood cells, white blood cells, platelets, and plasma. 

Red blood cells or erythrocytes are responsible for carrying oxygen from the lungs to the rest of the body. 

White blood cells or leukocytes are part of the immune system and help to fight off infections and diseases. 

Platelets are responsible for clotting the blood to prevent excessive bleeding. 

Plasma is a yellowish liquid that makes up about 55% of blood volume and contains important proteins, electrolytes, and hormones and waste products.

Blood is also classified into different types, based on the presence or absence of specific proteins on the surface of red blood cells. The four main blood types are A, B, AB, and O. 

Additionally, blood may be either Rh-positive or Rh-negative, depending on the presence or absence of another protein on red blood cells.

Blood vessels

Blood vessels are a pipe-like structure made to carry and return blood throughout our body. There are 3 types of blood vessels in our body. Arteries, Veins, and Capillaries.

Arteries Blood vessels carry blood from the heart to the rest of the body. Arteries are spread throughout the body. They have very high blood pressure, so their walls are thick. The main artery of our body is called aorta.

Veins Blood vessels carry blood from all over the body back to the heart. The lines that appear just below the skin in the hands and feet are veins. They have low blood pressure, so their walls are thin.

Capillaries are blood vessels that connect arteries and veins. The end of the artery remains connected to the end of the vein.

Pulse 

When the blood enters the arteries with pressure force, then the arteries expand slightly, that is called pulse.  heartbeats and pulse Both are equal.

heartbeats = pulse = 70 - 80/minute. whenresting.

Heart beat = pulse = 70 - 80/min - while at rest.

 Heart rate chart, while at rest.  

Looking at the heart rate table, it is clear that with increasing age, the heart rate rate also decreases. In other words, we can also say that increased heart rate means faster blood circulation, which helps oxygen and nutrients to reach the cells, tissues of the body faster. Fetuses and young children require more nutrients for their development.                  

• Adult heart rate - 70 - 80 per minute;
• 7 - 15 years - 80 - 90 per minute;
• 2 - 3 years - 100 - 115 per minute;
• 1 year - 115 - 130 per minute;
• Neonatale - 130 - 140 per minute;
• Foetus - 140 - 150 per minute.

• The average adult human body contains about 5 liters (or 1.3 gallons) of blood.
• Blood is composed of different components, including red blood cells, white blood cells, platelets, and plasma.
• Red blood cells are the most abundant type of blood cell and are responsible for carrying oxygen from the lungs to the rest of the body.
• White blood cells are part of the immune system and help to fight off infections and diseases.
• Platelets are responsible for clotting the blood to prevent excessive bleeding.
• Plasma is a yellowish liquid that makes up about 55% of blood volume and contains important proteins, electrolytes, and hormones.
• Blood types are determined by the presence or absence of specific proteins on the surface of red blood cells, which can be A, B, AB, or O.
• The Rh factor is another protein that can be present on red blood cells, and people who have it are considered Rh-positive, while those who don't are Rh-negative.
• Blood transfusions are sometimes necessary when a person loses a significant amount of blood, and it's important to match the donor's blood type and Rh factor with the recipient's to avoid adverse reactions.
• Regular blood donations are critical for maintaining an adequate supply of blood for medical procedures and emergencies.

How Much Blood is in the Human Body

The amount of blood in the human body depends on the size of the person's body, the larger the body, the more blood there is. A newborn baby will only have about a cup of blood in its body while a 68 -81 kg adult will have about 4.5 -5.6 liters (or 10-12 units) of blood in his body. Blood accounts for about 10% of an adult's weight.

Red blood, courtesy white blood cells and platelets, make up about 45% of our blood's volume, and the remaining 55% is fluid.

The Life-giving Fluid: Discovery of the Composition and Types of Blood in the Human Body

 Blood is a red colored liquid that flows in the blood vessels and circulates in the body. It contains a red pigment called haemoglobin, due to which the color of the blood is red. Blood has 4 components, plasma, red blood cells, white blood cells and platelets. Plasma is the liquid part of blood, and red blood cells, white blood cells, and platelets float in it.
The liquid part of blood is called plasma. It is a pale yellow, viscous liquid. It contains 90% water and 3.5% salt.
Red blood cells are red in color due to hemoglobin. Their function is to supply oxygen to different parts of the body.
White blood cells (the technical term leukocyte) fight infection and protect us from disease. White blood cells make chemicals called antibodies to fight infection.
Platelets help in blood clotting in cuts. If there are no platelets in our body, even in a minor cut, bleeding from the body will not stop and life can also be lost.
In an adult body, about 1 lakh kilometers of blood vessels pass through the body.

Blood composition and function: 

Blood performs many important functions in our body.

• Blood helps carry oxygen and carbon dioxide between the respiratory system and cells. Blood helps to carry stored food and vitamins to the cells or organs and tissues. It helps transport waste products from tissue cells to the excretory organ and regulates water balance. It contains antibodies to fight infection in the body.
• It helps in transporting nutrients and water to all parts of the body. It prevents excessive bleeding in case of accidents by forming blood clots. It transports hormones from the glands to the parts where it is needed for action. It helps in regulation of an organism and distribution of heat evenly throughout the body.

The color of the blood of all human beings is red, but it varies from person to person. Red blood cells contain protein molecules called antigens. These antigens are responsible for the formation of antibodies in the body. Antibodies are chemical substances. They form the human immune system. These antibodies are reactive to foreign substances. There are different types of blood depending on the antigens and antibodies present in the body.

Antigens are found on the surface of red blood cells and antibodies are present in the plasma. There are 4 types of blood groups in humans on the basis of antigens and antibodies.

A Blood group

A antigen- B antibody- donate blood A and AB- receive blood A and O

B Blood group

B antigen-A  antibody- donate blood B and AB-receive blood B and O

AB Blood group

A and B antigen- none  antibody- donate blood AB- receive blood AB, A, B, and O

O Blood group 

antigen none- A and B  antibody- donate blood A, B, O, and AB- receive blood O

Rhesus factor or Rh factor

There is another antigen in the blood which is the Rhesus factor. This determines the compatibility of the blood transfusion to be given to the recipient.

The Rhesus factor can be positive or negative. The plasma of an Rh negative person does not contain antibodies against the Rh factor.