Blood has three main functions: transport, protection, and regulation. It transports gases, nutrients, hormones, heat, and waste throughout the body. Blood also protects the body through white blood cells that destroy pathogens and platelets that initiate clotting. Additionally, blood helps regulate pH, water balance, and other processes. Blood is composed of plasma, red blood cells, white blood cells, and platelets, each with distinct roles in these important functions.

1. ENES BABAOĞLU
CIU
3RD SEMESTER

2. Blood is a constantly circulating fluid providing the body with nutrition,
oxygen, and waste removal. Blood is mostly liquid, with numerous cells
and proteins suspended in it, making blood "thicker" than pure water.
The average person has about 5 liters (more than a gallon) of blood.
A liquid called plasma makes up about half of the content of blood.
Plasma contains proteins that help blood to clot, transport substances
through the blood, and perform other functions. Blood plasma also
contains glucose and other dissolved nutrients.

3. Blood has three main functions: transport, protection and regulation.
TRANSPORT
Blood transports the following substances:
Gases, namely oxygen (O2) and carbon dioxide (CO2),
between the lungs and rest of the body
Nutrients from the digestive tract and storage sites to the
rest of the body
Waste products to be detoxified or removed by the liver and
kidneys
Hormones from the glands in which they are produced to
their target cells
Heat to the skin so as to help regulate body temperature

4. PROTECTION
Blood has several roles in inflammation:
Leukocytes, or white blood cells, destroy invading microorganisms and
cancer cells
Antibodies and other proteins destroy pathogenic substances
Platelet factors initiate blood clotting and help minimise blood loss
REGULATION
Blood helps regulate:
pH by interacting with acids and bases
Water balance by transferring water to and from tissues

5. RED BLOOD CELLS
• The blood cells that carry oxygen. Red cells contain hemoglobin and it is the hemoglobin
which permits them to transport oxygen (and carbon dioxide). Hemoglobin, aside from being
a transport molecule, is a pigment. It gives the cells their red color (and their name).
• The abbreviation for red blood cells is RBCs. Red blood cells are sometime simply called red
cells. They are also called erythrocytes or, rarely today, red blood corpuscles
• Hemoglobin is the protein inside red blood cells that carries oxygen. Red blood cells also
remove carbon dioxide from your body, transporting it to the lungs for you to exhale.
• Red blood cells are made inside your bones, in the bone marrow. They typically live for about
120 days, and then they die

6. WHITE BLOOD CELLS
• White blood cells are an important component of your blood system, which is also made up of red blood cells,
platelets, and plasma.
• Although your white blood cells account for only about 1% of your blood, their impact is significant. White blood
cells, also called leukocytes, are essential for good health and protection against illness and disease.
• Think of white blood cells as your immunity cells. In a sense, they are continually at war. They flow through your
bloodstream to battle viruses, bacteria, and other foreign invaders that threaten your health. When your body is
in distress and a particular area is under attack, white blood cells rush in to help destroy the harmful substance
and prevent illness.
• White blood cells are made inside the bone marrow and stored in your blood and lymphatic tissues. Because
some white blood cells have a short lifespan of one to three days, your bone marrow is constantly making them.
• Among your white blood cells are:
• Monocytes.
• Lymphocytes.
• Neutrophils
• Basophils.
• Eosinophils.

9. PLATELETS
• Platelets, also called thrombocytes, are membrane-bound cell fragments. Platelets have no
nucleus, they are between one to two micrometers in diameter, and are about 1/10th to
1/20th as abundant as white blood cells. Less than 1% of whole blood consists of platelets.
They result from fragmentation of large cells called Megakaryocytes - which are cells derived
from stem cells in the bone marrow.Their production is regulated by the hormone called
Thrombopoietin. The circulating life of a platelet is 8–10 days. The sticky surface of the
platelets allow them to accumulate at the site of broken blood vessels to form a clot. This
aids in the process of hemostasis ("blood stopping"). Platelets secrete factors that increase
local platelet aggregation.

10. BLOOD TYPE
There are four main blood groups defined by the ABO system:
blood group A has A antigens on the red blood cells with anti-B antibodies in
the plasma
blood group B has B antigens with anti-A antibodies in the plasma
blood group O has no antigens, but both anti-A and anti-B antibodies in the
plasma
blood group AB has both A and B antigens, but no antibodies
Receiving blood from the wrong ABO group can be life threatening. For
example, the anti-A antibodies in a recipient with group B blood will attack
the group A cells if transfused to them. This is why group A blood must
never be given to a group B person.
As group O red blood cells don't have any A or B antigens, it can safely be
given to any other group.

11. RH SYSTEM
• Receiving blood from the wrong ABO group can be life threatening. For example,
the anti-A antibodies in a recipient with group B blood will attack the group A cells
if transfused to them. This is why group A blood must never be given to a group B
person.
• As group O red blood cells don't have any A or B antigens, it can safely be given to
any other Group
• A RhD positive (A+)
• A RhD negative (A-)
• B RhD positive (B+)
• B RhD negative (B-)
• O RhD positive (O+)
• O RhD negative (O-)
• AB RhD positive (AB+)
• AB RhD negative (AB-)