Components of
BLOOD
Functions of the Blood

The big function of the blood is to carry
oxygen to the body's tissues. The blood
also plays parts in fighting infection,
temperature regulation, fluid and
electrolyte balance, and maintenance of
optimal pH.
Blood Components

The blood is made up of several different
components and types of cells.

The stem cell for all blood cells is the
hemocytoblast.
Separating Blood Components
Place vials of blood in a centrifuge.
 Centrifuge spins blood – heavier components
move to bottom of vials and lighter components
remain on top

Composition of Blood
Plasma
The liquid portion of the blood.
 Made up mostly of water, but also contains nutrients,
electrolytes, hormones and cellular wastes.
 Plasma carries gases as well (oxygen, carbon dioxide
and nitrogen).
 The plasma also contains three proteins which are made
by the liver.
 Albumin is a large protein which exerts osmotic pressure
that pulls fluid into the blood.
 Globulin transports lipid soluble vitamins (A, D, E and K)
and has an antibody role.
 Fibrinogen is a necessary protein in blood coagulation.

Leukocytes
a.k.a. White Blood Cells (WBC)
 There are five types.
 White blood cells are divided into two
groups: Granulocytes and agranulocytes.
 Granulocytes have granules visible inside
the cell – little sacs containing enzymes,
compounds that digest microorganisms. .
 Agranulocytes have no visible granules.

Types of Leukocytes

Leukocytes are formed in the red bone
marrow. Agranulocytes undergo further
development in the lymphatic tissue.

In order of most to least populous
leukocytes: neutrophils, lymphocytes,
monocytes, eosinophils, basophils (Never
Let Monkeys Eat Bananas).
Neutorphils
The most numerous of the
white blood cells, normally
making up about 65-70%
of the total white blood
cell count.
 Neutrophils are granulocytes whose granules do
not pick up a predominant
color when stained with
Wright stain (Neutral).
 Neutrophils fuction as
phagocytes

Lymphocytes
Make up 20-25% white
blood cell count, and are
easily distinguishable by
the large nucleus which
takes up almost all of the
cell.
 Lymphocytes are
agranulo-cytes.
 Lymphocytes are involved
in immune responses
(form anitbodies) and are
further differentiated into
T-lympho-cytes and Blymphocytes.

Monocytes
Large cells with a kidneyshaped nucleus that make
up about 4-8% of the
total white blood cell
population.
 Monocytes are agranulocytes.
 Monocytes function as
phagocytes, and develop
into macrophages.

Eosinophils
Granulocytes that stain red
with Wright Stain.
 Nucleus looks like a droopy
figure 8.
 Eosinophils are involved in
dissolving clots and also
function in allergic
reactions.
 Make up 2-5% of white
blood cells

Basophils
Granulocytes that stain blue
with Wright Stain.
 Basophils make up the
smallest portion of the total
white blood cells - 0.5 - 1%.
 They release heparin and
later develop into mast cells
which are involved in the
inflammatory response.
 Basophils also release
serotonin.

Thrombocytes
a.k.a. Platelets
 Thrombocytes are
actually fragments of
cells.
 They are formed in
the red bone marrrow
and live about 10
days.
 Thrombocytes
function in clotting.

Erythrocytes
a.k.a. Red Blood Cells (RBC)
 biconcave disks that lack a
nucleus
 Each red blood cell contains
Hemoglobin
 The iron in the hemoglobin
molecule forms complexes
with oxygen which allows the
blood cell to transport the
oxygen to the tissues.
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Erythrocytes live about 120 days before being
destroyed in the liver and spleen.
The iron in the red blood cells is conserved and
recycled.
Formation: Formed by a process called
erythropoiesis.
Erythropoietin is a hormone released by the
kidneys and liver which stimulates the
differentiation of stem cells into proerythroblasts.
The formation of red blood cells take place in the
red bone marrow.
This hormone release is controlled by a negative
feedback cycle driven by low oxygen
concentrations (hypoxia).
Comparing Blood Cells
Specifics