Chapter #12 Blood

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Transcript Chapter #12 Blood

Chapter #12
Blood
12.1
 Blood is a type of connective tissue
whose cells are suspended in a liquid
material.
12.2

Whole blood is:
I.
Slightly heavier than water
II.
3 to 4 times more viscous (resistance
to flow)
Blood cells form mainly in the red bone
marrow.
Blood also contains cells (RBC and WBC)
and cell fragments (platelets) called
formed elements.
 The average sized adult has about 5
liters of blood volume.
 Men have more blood than women.
 Men 1.5 gallons, women 0.875 gallons.
 A blood sample is usually about 45%
cells (red and white) this is called the
hematocrit (HCT).
 A blood sample is about 55% liquid
called plasma (yellow in color).
 Plasma (nonliving) is a complex mixture
of water (92%), amino acids, proteins,
carbohydrates, lipids, vitamins,
hormones, electrolytes, and cellular
wastes.
In one drop of blood
 RBC 5 million, live for 120 days, main
job is to carry oxygen.
 WBC 8,000, live for 10 days, main job is
to fight infections.
 Platelets 250,000, 5 days, main job is to
aid in forming clots.
Red Blood Cells

RBC or erythrocytes are biconcave
disks, shaped like donuts with no hole.
 Hemoglobin
i. is the protein that causes blood to be
red.
ii. carries oxygen on the RBC.
 Anemia is having too few RBC or too
little hemoglobin. A person with anemia
feels tired, is short of breath, and looks
pale.
 The production of RBC is dependent on
adequate intake of iron, folic acid,
vitamin B12.
 RBC lack a nucleus and therefore
cannot synthesize proteins or reproduce.
Sickle Cell

Sickle cell anemia is a genetic disease
in which all the RBC are shaped like
sickles.
i. Sickle cell is more common among
African-Americas.
ii. People with sickle cell have serious
health problems.
iii. Sickle cells do not carry enough
oxygen and can get stuck in blood
capillaries.
Destruction of RBC
 Marcrophages destroy damaged RBC,
primarily in the liver and spleen.
White Blood Cells
 WBC or leukocytes protect against
disease.
 There are 5 types of WBC. They are
classified according to size, the nature of
their cytoplasm, nuclei shape, and how
they stain.
2 Main Groups of WBC
1. Granulocytes are leukocytes with
granular cytoplasm. They live only
about 12 hours.
2. Agranulocytes are leukocytes without
cytoplasmic granules.
5 types of WBC
1. Neutrophils is the most numerous WBC.
2. Eosinophils are WBC that increase in
certain parasitic infections and allergic
reactions.
3. Basophils release heparin and histamine.
4. Monocytes are the largest blood cells.
They are 2 or 3 times larger than RBC.
5. Lymphocytes can live for many years.
They form antibodies necessary for
immunity to specific diseases.
 WBC combat infection by phagocytes
and antibody production.
WBC diseases
 Leukemia is a form of cancer
characterized by uncontrolled production
of WBC.
 AIDS or Acquired Immune Deficiency
Syndrome, is a disease of the immune
system. The AIDS virus reproduces in
only one kind of WBC.
Platelets
 Platelets or thrombocytes are not
complete cells.
 Platelets lack a nucleus.
 Platelets help close breaks in damage
blood vessels and initiate formation of
blood clots.
12.3 Blood Plasma
 Plasma is the clear, straw colored, liquid
portion of the blood.
 Plasma is 92% water.
 Functions included transporting
nutrients, gases, and vitamins. Help
regulate fluid and electrolyte balance
and maintaining body pH.
Plasma Proteins
 Plasma proteins are the most abundant

1.
2.
3.
of the dissolved substances in plasma.
3 Types of Plasma Proteins
Albumins
Globulins
Fibrinogen
 Albumins are the smallest of the plasma
proteins, account for 60% of these
proteins by weight. Made in the liver.
 Globulins make up 36% of plasma.
Produce by lymphatic tissue
(Lymphocytes).
 Fibrinogen make up 4% of plasma.
Functions in blood coagulation.
Gases and Nutrients
 Blood Gases are oxygen and carbon
dioxide.
 Plasma nutrients include amino acids,
simple sugars, nucleotides, and lipids
absorbed from the digestive tract. Most
nutrients found in the plasma were
primarily absorbed from the small
intestines.
 Plasma lipids include fats, phospholipids,
and cholesterol. Lipids are not soluble in
water.
 Lipids that connect to proteins are called
lipoproteins.
 Lipids are transported in plasma
primarily as lipoproteins.
Cholesterol
 (LDL) Low-Density lipoproteins (bad)
 (HDL) High-Density lipoproteins (good)
 Nonprotein nitrogenous substances
include amino acids, urea, and uric acid.
 Plasma Electrolytes are absorbed from
the intestine. Sodium, potassium,
calcium, magnesium, chloride,
bicarbonate, phosphate, and sulfate
ions. Na and Cl are the most abundant.
12.4 Hemostasis
 Is the stoppage of bleeding.
 Vasospasm when severed vessel close
completely only last up to 30 minutes.
 Serotonin release which causes smooth
muscles to contract that reduces blood
loss.
 Platelets adhere to any rough surface
and form blood clots. Clots begin to form
when platelets come in contact with a
rough surface.
Blood Coagulation
 Coagulation the most effective
hemostatic mechanism, causes
formation of blood clots.
 Fibrin insoluble threads.
 Prothrombin produced by the liver. In the
presence of Calcium ions converts into
thrombin which then forms fibrin threads.
Platelet disease
 Hemophilia- genetic disease in which
blood is missing the clotting factor. Blood
transfusions prior to 1985 have caused
95% of the hemophiliacs to develop
AIDS.
 Von Willebrand- genetic disease in which
a plasma protein in missing causes
people to bruise and bleed easily.