PHYSIOLOGY- 2 MARKS- PART 2:

COAGULATION TIME:

The coagulation time is a measurement of the intrinsic power of the blood to convert fibrinogen to fibrin.
PT (The prothrombin time ) is measured in seconds. Most of the time, results are given as what is called INR(international normalized ratio).
If you are not taking blood thinning medicines, such as warfarin, the normal range for your PT results is: 11 to 13.5 seconds.

BLEEDING TIME:

Bleeding time is a laboratory test to assess platelet function and the body’s ability to form a clot.
The test involves making a puncture wound in a superficial area of the skin and monitoring the time needed for bleeding to stop.
Platelets are tiny cell fragments that circulate in your blood.
They’re the first cells to react to a blood vessel injury.
They seal off the wound to prevent more blood from escaping.

IMPORTANCE OF COAGULATION OF BLOOD:

Blood clotting, or coagulation, is an important process that prevents excessive bleeding when a blood vessel is injured.
Platelets (a type of blood cell) and proteins in your plasma (the liquid part of blood) work together to stop the bleeding by forming a clot over the injury.

RED BLOOD CORPUSCLES:

Red Blood Cells also called erythrocytes or RBCs.
Known for their bright red color, red cells are the most abundant cell in the blood, accounting for about 40 to 45 percent of its volume.
The shape of a red blood cell is a biconcave disk with a flattened center. Production of red blood cells is controlled by erythropoietin, a hormone produced primarily by the kidneys.
The red blood cell survives on average only 120 days.
Red cells contain a special protein called hemoglobin, which helps carry oxygen from the lungs to the rest of the body and then returns carbon dioxide from the body to the lungs so it can be exhaled.

WHITE BLOOD CORPUSCLES:

White blood cells protect the body from infection.
They are much fewer in number than red blood cells, accounting for about 1 percent of your blood.
The most common type of white blood cell is the neutrophil, which is the “immediate response” cell and accounts for 55 to 70 percent of the total white blood cell count.
The other major type of white blood cell is a lymphocyte. There are two main populations of these cells.
T lymphocytes help regulate the function of other immune cells and directly attack various infected cells and tumors.
B lymphocytes make antibodies, which are proteins that specifically target bacteria, viruses, and other foreign materials.

PLATELETS:

PLATELETS also called thrombocytes.
Unlike red and white blood cells, platelets are not actually cells but rather small fragments of cells.
Platelets help the blood clotting process (or coagulation) by gathering at the site of an injury, sticking to the lining of the injured blood vessel, and forming a platform on which blood coagulation can occur.
A higher than normal number of platelets can cause unnecessary clotting, which can lead to strokes and heart attacks
Conversely, lower than normal counts can lead to extensive bleeding.

BLOOD VOLUME:

In an average healthy adult, the volume of blood is about one-eleventh of the body weight.
Most sources state the volume of blood in an average human adult, who is between 150 to 160 pounds ( 70KGS TO 80 KGS), as between 4.7 and 5 liters, although the more recent sources state the volume of blood in an average adult as 4.7 liters.

FUNCTIONS OF HEMOGLOBIN:

Hemoglobin is contained in red blood cells, which efficiently carries oxygen from the lungs to the tissues of the body.
Hemoglobin also helps in the transportation of carbon dioxide and hydrogen ions back to the lungs.

ANAEMIA:

A person with anaemia doesn’t have enough haemoglobin in their blood or has fewer red blood cells than normal.
Symptoms of anemia will vary depending on the type and cause, but include:
Fatigue and loss of energy
Unusually rapid heartbeat, particularly with exercise
Shortness of breath and headache, particularly with exercise
Difficulty concentrating
Dizziness
Pale skin
Leg cramps
Insomnia.

Catherine Shalini Raja - Happy To Serve