Download Blood - Cobb Learning

Blood
Characteristics of Blood



Connective tissue
Plasma and cells
Transports
substances between
body cells and the
external
environment
Blood Volumes



Varies with body size
(type), fluid and
electrolyte
concentrations, and
amount of adipose (fat)
Average adult volume
– 5 liters (4-5 L for
women, 5-6 L for men)
Hematocrit – usually
45%
Blood Cell Types



Erythrocytes – Red
blood cells
Leukocytes – White
blood cells
Thrombocytes platelets
Red Blood Cells (RBCs)

Biconcave disks
that thin near the
centers



increased surface
area for transporting
gases
Have nuclei early in
development, but
extrude them
No nucleus – more
room for
hemoglobin, but
cannot reproduce or
make proteins
Hemoglobin







Oxygen-carrying
protein
1/3 of each RBC
Gives blood its color
Oxyhemoglobin
Deoxyhemoglobin
Hypoxia
Cyanosis
Red Blood Cell Counts





RBCC – the number of
RBCs in 1 mm3 of blood
Adult male average –
4.6 – 6.2 million
Adult female average –
4.2 – 5.4 million
Determines blood’s
oxygen carrying capacity
Important diagnostic tool
Blood Cell Production



RBCs are normally
flexible, elastic, and
able to pass through
small blood vessels
More fragile as they
age
Macrophages
phagocytize and
destroy damaged
RBCs in the liver
and spleen in about
120 days
White Blood Cells (WBCs)

Function to protect
against disease




Phagocytize bacterial
cells
Produce antibodies
Move by diapedesis
2 main types:


Granulocytes –
neutrophils, eosinophils,
and basophils
Agranulocytes –
monocytes and
lymphocytes
Granulocytes - Neutrophils




Lobed nucleus with
2-5 sections
Dark staining
nucleus and pale
granules
54-62% of WBCs
Contain many
lysosomes – actively
phagocytizes
bacteria
Granulocytes - Eosinophil






Contains coarse,
uniformly sized
granules
2 lobes on nucleus
Stains red
1-3% of WBCs
Kills parasites
Helps control
inflammation and
allergic reactions
Granulocyte - Basophils




Fewer, more irregular
granules than
eosinophils
Granules stain deep
blue
Less than 1% of WBCs
Contain heparin (inhibits
blood clotting) and
histamine (increases
blood flow to injured
tissues)
Agranulocytes - Monocytes




Largest blood cells
May live weeks to
months
3-9% of WBCs
Change to
macrophages in
tissue
Agranulocyte - Lymphocytes






Form in red bone marrow
and lymphatic system
Slightly larger than RBCs
Large, round nucleus with
rim of cytoplasm
May live for years
25-33% of WBCs
Important for immune
response
White Blood Cell Count (WBCC)





Number of WBCs in 1
mm3 of blood
Adult average – 5000 –
10,000 cells
Leukocytosis – high
count
Leukopenia – low
count
Differential WBCC
(DIFF)



More neutrophils –
bacterial infection
More eosinophils –
parasitic infection,
allergic reaction
Leukemia
Platelets








Not complete cells
Form from
megakaryocytes that
fragment
Lack nuclei
Half size of RBCs
Live 10 days
Average count –
300,000/mm3
Help close breaks in
damaged blood vessels
Initiate formation of blood
clots
Plasma


92% water
Functions include:



Transporting
nutrients, gases, and
vitamins
Regulating fluid and
electrolyte balance
Maintaining pH
Hemostasis





Step 1: Vascular
spasms
Step 2: Platelet plug
formation
Step 3: Coagulation
Step 4: Fibroblasts
invade clot
Process takes 3-6
minutes
Hemostasis
Normally clots are good, but an embolism is a clot that
dislodges and travels elsewhere in the body. This can result in a
coronary (heart) or a stroke (brain).
Blood Disorders
 Normally clots are good, but an embolism is a clot
that dislodges and travels elsewhere in the body.
This can result in a coronary (heart) or a stroke
(brain).
 A brain (cerebral) aneurysm is a bulging, weak
area in the wall of an artery that supplies blood to
the brain. In most cases, a brain aneurysm causes
no symptoms and goes unnoticed. In rare cases,
the brain aneurysm ruptures, releasing blood into
the skull and causing a stroke.
Blood Groups


ABO blood group is
based on the presence
or absence of 2 major
antigens (RBC surface
molecules)
4 possible combinations:




A
B
AB
O
video
Rh Blood Group
85% people are Rh+
Rhesus (Rh) factor is an inherited protein found on
the surface of red blood cells. If your blood has the
protein, you're Rh positive. If your blood lacks the
protein, you're Rh negative.