11.2 Blood Flashcards
Human blood consists of 2 main components
Cellular and intercellular component
Cellular component
red blood cells, white blood cells and platelets
Intercellular component
Yellow coloured liquid called plasma
What separates blood into its components
Centrifuge
Plasma
Protein rich liquid in white blood cells and platelets
Over 90% of plasma is water
Dissolved in plasma is oxygen, protein, nutrients, minerals, vitamins, CO2 and waste product
Proteins in plasma
Albumins, globulins and fibrinogen
Albumins
Controls water balance
Globulins
Transports lipids and includes antibiotics
Fibrinogen
Role in blood clotting
Red blood cells
They are very tiny
The main function of the red blood cells is to carry oxygen from the lungs to the body and carry back CO2 to be expelled.
Red blood cells are formed from stem cells in the marrow of vertebrae, ribs, breastbone, skull and arm/leg bones.
They mature, the nucleus breaks down, making more space for hemoglobin
Eventually, they die after after 120 days
White blood cells
These are also formed in bone marrow
There are various types of white blood cells
They are the first line of defense against bacteria, viruses and other harmful organisms.
2 types of white blood cells
Granular and agranular
Granular white blood cells
Small particles or grains in their cytoplasm to attack foreign materials and microorganisms
Agranular white blood cells
Aka “Lymphocytes” and “Monocytes:, specialized for engulfing bacteria and other microorganisms.
Platelets
Platelets are small cell fragments produced from stem cells in bone marrow.
They are in charge of blood clotting or “Conjugation”.
When a blood vessel breaks, chemicals in the platelets cause the platelets to stick to collagen fibers in the blood vessel wall.
As more and more stick, a temporary clot is in place.
Fibrinogen in the plasma is converted to long strands of fibrin, forming a mesh trap to catch more platelets.
If the clot breaks off and enters the bloodstream, it can block off a blood vessel.
If this happens to the brain, a stroke can occur.
Counting red blood cells
When a blood sample is taken, doctors do a complete blood count “CBC”.
A hemocytometer can predict erythrocytes, leukocytes and platelets in a given volume.
Anemia: red blood cell count is lower than expected
Causing fatigue, most commonly caused by low iron.
A high leukocyte count is a sign of your body fighting infection
Also a sign of a blood cancer known as leukemia.
How we determine blood type
The presence of sugars or “Markers” in the blood on the cell membrane of erythrocytes.
Called “A” “B” markers
If your have both, your AB blood type
If your have neither, your O blood type
We need to transfuse similar blood types
If we put A blood in someone with type B Blood, the blood will build antibodies to fight the new blood.
What is the best blood type to give and receive
Give: O negative
Receive: AB
O negative blood has no antigens, it will not trigger an immune response, even if the recipient has a different blood type. AB can receive any type of blood as it has A and B both in it
Rhesus factor
An inherited factor, affecting compatibility of blood
Discovered while studying blood in rhesus monkeys
An antigen on erythrocyte membrane that produces an antibody reaction.
This is present in about 85% of population, and they’re known to be Rh-positive
The remaining 15% who don’t have it are called Rh-negative.
