Blood: Structure, Function, Components

Components:

1. i) plasma
   ii) erythrocytes (red blood cells)
   iii) leukocytes (white blood cells)
   iv) platelets

Plasma:
o    55% of blood volume and is 90% water
o    Contains dissolved materials which are being transported:
o    proteins (fibrinogen), hormones, nutrients, waste products, gases

Erythrocytes:
o    Function: > to carry oxygen
o    Structure: >  no nucleus, cytoplasm contains mostly hemoglobin molecules

o    biconcave shape; allows for flexibility and movement through vessels of different shapes and sizes

Hemoglobin

Complex protein molecule made up of four protein chains, with an iron at the core of each chain
o    iron is the key component of hemoglobin that binds oxygen
o    Other info:  are constantly being destroyed and replaced
o    because no nucleus, have a lifespan of about 4 months (120 days)
o    two million cells are destroyed every second

Leucocytes:
o    Function: help defend the body from disease and infection
o    Structure: amoeboid-shaped cells destroy and consume invading bacteria and damaged body cells

Plateletes:
o    Function: >  assist in blood clotting process
o    cell fragments that have broken off from special cells in the bone marrow
o    Clotting    i) when platelets encounter damaged blood vessels, they break open and release chemicals called clotting factors into the blood
•    ii) factors help platelets to stick together to from a platelet plug
•    iii) blood proteins then form fibrin molecules around the platelet plug
•    iv) fibrin molecules form a mesh trapping blood cells and prevent them from passing through the damaged blood vessel

Other info:
o    erythrocytes, leukocytes and platelets are manufactured in the bone marrow
o    cellular components of blood make up 45% of the blood volume
o    red blood cells are the most abundant cells in the blood (for every white blood cell in the blood there is 1000 red blood cells)
Anemia:
o    when there is a decreased amount of hemoglobin in the blood
o    can be caused by:                i) blood loss
ii) too few red blood cells being produced
iii) reduced amounts of hemoglobin molecules in red blood cells

Shock:
o    when circulatory system can not meet the nutritional needs of vital organs
o    if nutritional needs of vital organs can not be met, the organs will shut down

Components: i) plasma

1. ii) erythrocytes (red blood cells)

iii) leukocytes (white blood cells)

1. iv) platelets

Plasma:

• 55% of blood volume and is 90% water
• Contains dissolved materials which are being transported:
• proteins (fibrinogen), hormones, nutrients, waste products, gases

Erythrocytes:

Function: to carry oxygen

Structure: no nucleus, cytoplasm contains mostly hemoglobin molecules

biconcave shape; allows for flexibility and movement through vessels of different shapes and sizes

Hemoglobin: complex protein molecule made up of four protein chains, with an iron at the core of each chain

iron is the key component of hemoglobin that binds oxygen

Other info: are constantly being destroyed and replaced

• because no nucleus, have a lifespan of about 4 months (120 days)
• two million cells are destroyed every second

Leukocytes:

Function: help defend the body from disease and infection

Structure: amoeboid-shaped cells destroy and consume invading bacteria and damaged body cells

Platelets:

Function: assist in blood clotting process

cell fragments that have broken off from special cells in the bone marrow

Clotting i) when platelets encounter damaged blood vessels, they break open and release chemicals called clotting factors into the blood

1. ii) factors help platelets to stick together to from a platelet plug

iii) blood proteins then form fibrin molecules around the platelet plug

1. iv) fibrin molecules form a mesh trapping blood cells and prevent them from passing through the damaged blood vessel

Other info:

erythrocytes, leukocytes and platelets are manufactured in the bone marrow

cellular components of blood make up 45% of the blood volume

red blood cells are the most abundant cells in the blood (for every white blood cell in the blood there is 1000 red blood cells)

Anemia:

when there is a decreased amount of hemoglobin in the blood can be caused by:

1. i) blood loss
2. ii) too few red blood cells being produced
3. iii) reduced amounts of hemoglobin molecules in red blood cells

Shock:

when circulatory system can not meet the nutritional needs of vital organs if nutritional needs of vital organs can not be met, the organs will shut down