Download chapter 9-blood, lymph and immune systems

CHAPTER 9-BLOOD, LYMPHATIC AND IMMUNE SYSTEMS
I. FUNCTIONS OF THE BLOOD
A. Transports molecules through the body.
B. Maintains fluid balance in the body.
C. Regulates body temperature.
D. Produces blood clots.
E. Fights infection and provides immunity.
II. GENERAL POINTS ON BLOOD
A. An average adult contains about 5 Liters of blood (8% of total body weight).
B. We replace blood at a rapid pace.
C. Components of Blood:
1. Plasma-the liquid portion of blood.
2. Formed Elements-the blood cells.
III. STRUCTURE AND FUNCTION OF THE BLOOD
A. Plasma-the liquid portion of blood, makes up about 55% of total blood volume.
1. It is mostly water (92%) in composition but it does contain a variety of dissolved
compounds (proteins, gases).
2. A number of important proteins are carried through the body by plasma. Some of
these proteins include:
a. Alpha globulins-carry fats through the body.
b. Gamma globulins-involved in immune responses.
c. Globulins can be separated from plasma by forcing an electrical charge
through plasma. This process is known as electrophoresis.
3. Plasmapharesis-process using a centrifuge to separate plasma from blood cells.
4. Plasma also carries fibrinogen and plasmin through the body. These are two
important clotting proteins. Coagulation-clot formation.
a. Heparin-a common anticoagulant; prevents clot formation.
B. Formed Elements in Human Blood
1. Erythrocytes-Red blood cells.
a. These function by carrying oxygen to body tissues from the lungs and
carbon dioxide from the body to the lungs.
b. Hemoglobin-red pigment in erythrocytes that is involved in carrying
oxygen to the body. It is composed of an iron-containing portion known
as a heme and a protein known as globin.
c. Hematocrit-measurement of the percentage of red blood cells in blood.
d. Hemocytoblasts-stem cells in bone marrow that develop into all blood
cells.
e. Old and damaged red blood cells are removed by the spleen.
2. Leukocytes-White blood cells.
a. These function by destroying foreign agents in the human body. In other
words these work to fight infection and provide immunity.
b. Types of Leukocytes:
1) Granulocytes-contain granules in their cells. Types of granulocytes
include:
a) Neutrophils-fight bacteria.
b) Eosinophils-attack parasitic worms.
c) Basophils-involved in inflammation responses.
2) Agranulocytes-do not contain granules. Types:
a) Lymphocytes-fight viruses, cancer cells.
b) Monocytes-develop into macrophages that engulf invaders.
3. Thrombocytes-Platelets
a. These are involved in blood clotting.
IV. 2 SYSTEMS OF HUMAN BLOOD TYPES
A. The ABO Blood System
1. Most red blood cells are covered by special proteins known as agglutinogens.
2. Antigen-protein on blood cells.
3. Antibodies-are involved in immune responses. These attack and kill foreign
materials in the body.
4. Based on these proteins, there are 4 recognized blood types that can occur in
humans: (see chart in textbook).
a) Type A individuals
b) Type B individuals
c) Type AB individuals-Universal Recipients
d) Type O individuals-Universal donors
B. The Rh Blood System-named for the Rhesus monkey.
1. Most people are Rh+, some are Rh-. This is most often discussed during pregnancy.
2. If an Rh- mother conceives an Rh+ child, the mother can build up antibodies against
the Rh+ blood. If the mother conceives a second Rh+ child, then the mother will
have an immune response against the baby (Erythroblastosis fetalis).
V. FUNCTIONS OF THE LYMPHATIC AND IMMUNE SYSTEM
A. It reduces edema by removing fluid from body tissues.
B. It moves certain proteins from the body to the blood.
C. It traps and filters microbes, cancer cells and wastes from the body. Special cells known as
macrophages help destroy these materials.
D. It recycles fluids to various parts of the body.
E. It carries lymphocytes to places in the body where they can participate in immune responses.
F. It moves fats from the digestive system to the blood.
G. It helps protect the body through immune responses and inflammation.
VI. LYMPHATIC STRUCTURES AND ORGANS
A. The lymphatic system is composed of a series of vessels (like the cardiovascular system)
and a number of special organs. The lymphatic system serves as a drainage system that
removes excess fluid from the body and as a immunity system.
B. Lymphatic Vessels-located throughout the body, these vessels function by draining fluid
from body tissues. These vessels carry the fluid to the cardiovascular system which
distributes the fluid throughout the body.
1. Once fluid enters a lymphatic vessel it is referred to as lymph.
2. Lymphatic vessels often contain valves to prevent the backflow of lymph.
3. Lymph Nodes-located along the length of lymphatic vessels.
a. These structures serve as filtering structures. That is, they act to filter
microbes, wastes and cancer cells out of the lymph as it passes by. Lymph
is not fully filtered until it passes through several lymph nodes.
b. Lymph nodes contain numerous lymphocytes and macrophages that destroy
microbes. Macrophages carry out this function by eating the invader by a
a process known as phagocytosis.
c. During a severe infection, lymph nodes will often swell and become tender.
d. Major collections of lymph nodes are found in the neck, the groin area and
under the arm.
C. The Spleen-largest lymphatic structure in the body, it is located on the left side of the
abdominal cavity.
1. The spleen functions by removing old and worn out red blood cells and in activating
lymphocytes to destroy foreign debris in the body.
2. The spleen also plays a role in producing B Lymphocytes.
3. If the spleen is injured, it can be removed. What structures assume the function of
the spleen at this point?
D. The Thymus Gland-located in the upper thoracic cavity.
1. This gland aids in the production of T Lymphocytes that destroy viruses.
2. This gland shrinks in size as we age. Usually by the age of 20, it is completely gone.
E. Tonsils-located on either side of the Pharynx (Throat)-trap dirt and pathogens.
VII. THE IMMUNE SYSTEM-protects the body from invading microbes, parasites, cancer cells and
foreign debris.
A. The body has a number of structures/devices that protect us from a wide range of pathogens.
1. These include structures such as the skin and mucous membranes. We also produce a
number of cells and chemicals that kill invaders when they enter the body. All of
these devices work well to protect us, however, they do not provide permanent
protection from these pathogens. These methods are said to be nonspecific. For long
term protection, our bodies turn to immunity or specific defenses to protect us.
B. 2 Types of Immunity
1. Cell-Mediated Immunity-involves the production of specialized T Cell Lymphocytes
that are capable of identifying and destroying microbes (especially viruses) that enter
the body. The foreign agents that enter the body are often referred to as antigents.
2. Antibody-Mediated Immunity (Humoral Immunity)-involves the production of
B Cell Lymphocytes that produce antibodies which attach to and aid in the removal
of an antigen.
a. Antibodies are special proteins that aid in immunity. Often times antibodies
are referred to as immunoglobulins. There are several types of
immunoglobulins involved in immunity.
C. Immunity can be acquired naturally or through artificial means.
1. Natural Immunity-occurs when the body’s natural defenses identify and destroy a
pathogen. Once the invader is destroyed, the body retains memory to quickly identify
and destroy the pathogen if it invades the body again.
2. Aquired or Artificial Immunity-occurs when an antigen is injected into the body for the
purpose of providing immunity. Vaccines are examples.
VIII. WORD ELEMENTS-pages 265-270.
IX. PATHOLOGY
A. Anemia
B. AIDS
C. Autoimmune diseases
D. Edema
E. Hemophilia
F. Infectious mononucleosis
G. Leukemia
H. Hodgkin disease
I. Kaposi sarcoma
X. DISEASES AND CONDITIONS-pages 275-280.
XI. PHARMACOLOGY