Chapter 10 Blood
Functions of Blood
• Transport waste and nutrients
• Fight diseases
• Maintain body temperature
• Maintain homeostasis
Components of Blood
• There are four major components of blood
tissue:
• Blood plasma: about 55% of blood
volume
• Red blood cells (erythrocytes): about
45% of blood volume – called the
hematocrit
• White blood cells (leukocytes)
• Platelets
Components of Blood
Buffy Coat
Components of Blood
• Fun Facts:
1. has a salty/metallic taste
2. has a pH of 7.35 to 7.45, making it
slightly basic or alkaline
3. has a temperature of 100.4°F or 38°C
4. 8% of body weight
5. 5 – 6 liters (6 quarts) in healthy males
Components of Blood: Plasma
• Plasma: the nonliving, liquid part of blood
• About 90% water
• Over 100 types of substances are
dissolved in the plasma, like…
• Proteins, carbohydrates, salts, oxygen,
carbon dioxide, hormones, urea,
cholesterol, ect.
• Functions include: transport everything &
maintain body temperature
Components of Blood: Plasma
• Plasma proteins make the greatest
percent of solutes in plasma.
• Plasma protein fun facts:
– Most are made in the liver with the exception
of antibodies and amino acid based hormones
– Examples include: antibodies, protein
hormones, clotting proteins, albumin
– Not assimilated into cells for metabolism
Components of Blood: Erythrocytes
• Erythrocytes, aka red blood cells aka RBC
• Function to transport molecular oxygen to cells
for respiration (aka energy production).
• They have no nucleus and are merely a
hemoglobin sac
• Hemoglobin=protein carrier of oxygen and
carbon dioxide
• 1000 to 1 rbc to wbc count
• 1 rbc x 250 million hemoglobin molecules x 4
oxygen molecules = 1 billion oxygen
molecules/rbc
Components of Blood: Erythrocytes
• Homeostatic imbalance: anemia
• A decrease in the oxygen-carrying
capacity of blood
• 1. RBC count too low
• 2. hemoglobin amounts too low
• See table 10.1, page 311
• Polycythemia: too many rbcs, usually from
bone marrow cancer (or living at high
altitudes) – impairs circulation due to high
viscocity
Components of Blood
Components of Blood: Leukocytes
• Leukocytes, aka white blood cells, aka WBC
• Function: annihilation of foreign material
• 4,000 – 11,000 per mm3, less than 1% blood
volume
• The only true cells in blood tissue
• Unlike RBCs, these guys can pass in and out
of the blood stream as issued by chemical
signals (chemotaxis)
• Move like ameboas (cytoplasmic streaming)
Components of Blood: Leukocytes
• Homeostatic imbalances
• Leukocytosis: too many WBC; usually an
indication of infection; above 11,000 cells/mm3
• Leukopenia: abnormally low WBC count; usually
a side effect from certain medications like
anticancer treatments or corticosteroids.
• Leukemia (“white blood”): bone marrow cancer
which produces great numbers of abnormal and
immature WBCs. This decreases immune
responses and causes death from secondary
infection.
Components of Blood: Leukocytes
Classes of WBC:
1. Granulocytes: have granules that appear
with Wright’s stain.
a. neutrophils: avid phagocytes (cell eaters) at
sites of acute infection. (acute= fast, but
short lived) (chronic= long term or recurring)
b. Eosinophils: allergy & parasitic worm
fighters!
c. Basophils: rarest wbc; contain histamines
which are chemicals that make blood vessels
“leaky” (inflamed) and attractive to other wbc.
Components of Blood: Leukocytes
Classes of WBC:
2. Agranulocytes: no visible granules when
stained.
a. lymphocytes: created and reside in
lymphatic tissue; produce antibodies; fight
tumors, viruses, and grafts.
b. monocytes: largest WBCs; they are mutant
teenage ninja cells that change into
macrophages with voracious appetites; longterm clean up crew for chronic illnesses.
Components of Blood: Leukocytes
Components of Blood: Platelets
• Platelets aka
megakaryocyte
fragments
• Function: to help clot
blood
• Not cells, but cell
fragments
• 300,000/mm3 of blood
Hematopoiesis
• Hematopoiesis: blood cell formation &
maturation.
• Takes place in red marrow of flat bones
and epiphyses of long bones.
• Form from the same type of cell called
stem cells, or HEMOCYTOBLASTS.
• All the cells start out as the same cell, but
can become many different kinds of cells.
• Once they start down one path, they
cannot go back!
Hematopoiesis
Hematopoiesis
Erythrocyte Development
• Hemocytoblast stem cell  myeloid stem
cell  immature RBC (with organelles) 
massive amounts of mitosis and
hemoglobin synthesis  organelle
rejection by the cell and implosion 
teenaged RBC (reticulocyte-still has ER)
 to blood stream  in two days changes
to a mature RBC (no ER)  fall apart in
100 – 120  go to spleen, liver for
digestion.
Hematopoiesis
• Hormones control the rate of erythrocyte
production.
• Erythropoietin – produced mainly by the
kidneys; follows negative feedback
mechanisms
• Low oxygen blood volumes stimulate
erythropoietin production in kidneys which
stimulates RBC production in bone
marrow until oxygen levels rise.
Hematopoiesis
• Leukocyte production is also controlled by
hormones.
• Colony stimulating factors and interleukins
are stimulated by inflammatory chemicals,
bacteria or toxins which stimulate the red
marrow to produce more WBC until the
situation has repaired itself.
• Platelets are regulated by thrombopoietin.
Hemostasis: blood clot formation
• Step 1 platelet plug formation: when
collagen fibers of endothelium are
exposed from damage, platelets can stick
to them then they call for more until a plug
is formed.
• Step 2 vascular spasms: platelets in the
plug release serotonin which causes blood
vessels to contract lowering blood volume.
• Step 3 coagulation…
Hemostasis: blood clot formation
• Step 3 coagulation: a series of hormones
and proteins released by the injured tissue
and platelets race to the injury, form a
fibrous net, close off blood vessels and
form a clot! Bam!
• See p 316 for more complex version of
this story. 
Hemostasis: Gone Wrong!
• 1. undesirable clotting:
– Thrombus: clot in an unaffected vessel. Can
be caused by…rough endothelium, a physical
blow, accumulation of cholesterol, poor
circulation. (cardiac thrombosis)
– Embolus: a runaway thrombus (cerebral
embolus)
Hemostasis: Gone Wrong!
• 2. bleeding disorders:
– thrombocytopenia: causes spontaneous
internal bleeding (petechiae); caused by
myeloid stem cell suppression (too few
platelets) or liver damage (no clotting factor
synthesis).
– Hemophilia: genetic disease where clotting
factors are not synthesized; free bleeding,
joint damage and disease from blood
transfusions are all symptoms.
Blood Groups
Blood Groups
• Antigen: protein that is recognized as a
foreign body; is on RBC cell membranes,
bacteria and virus surfaces. Typically we
recognize and don’t attack our own
antigens.
• Antibodies: chemicals in the blood
plasma that recognize and bind to foreign
antigens.
Blood Groups
• Agglutination: clumping process caused by
antibodies binding to foreign RBCs.
• Leads to: clotted blood, ruptured RBCs,
loss of oxygen, kidney failure.
• Side effects include: fever, chills,, nausea,
vomiting
• 30 common RBC antigens, but only ABO
and Rh give vigorous reactions.
Blood Groups
Blood Groups
Blood Groups
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Rh Blood Groups
Rh positve = have the Rh antigen*
Rh negative = don’t have the Rh antigen
Antibodies are formed after first blood
transfusion. Then the cells will rupture.
• Pregnancy and Rh-: first child will be born
fine, then antibodies form in the mother
that will affect subsequent Rh+ children.
Blood Groups