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BIOLOGY 20 CHAPTER 11 BLOOD AND IMMUNE SYSTEM
Nelson Pages 348 – 375
Dividing the cell into its parts (or fractions) is called cell
fractionation and is achieved by the process of centrifugation using a
centrifuge.
Average 70 kg person has about 5 L of blood
Blood
55 % fluid or plasma
45 % blood cells
Plasma
90 % H2O
Also:
Proteins, glucose, vitamins, minerals, dissolved gases, and waste products of metabolism
Types Functions
•Albumins •Osmotic balance – maintain H2O levels
•Globulins
(immunoglobulins)
•Antibodies, immunity
•Fibrinogen •Blood clotting
Red blood cells or RBC’s
Transport O2
Packed with hemoglobin
Greatly increases capacity of RBC to
carry O2, by 70 X
Heme – iron containing pigment
Globin – protein structure
Oxyhemoglobin - gives blood its red
color
RBC’s
Are biconcave
Greater surface area for gas exchange
Are enucleated (no nucleus) when
mature
More room for cell to carry hemoglobin
Are made in bone marrow –
erythropoieses
Are broken down by spleen and liver
Heme is transformed into bile pigments
Iron returns to liver for storage and bone
marrow for reuse
RBC’s and low O2 levels
Exercise, high altitude, hemorrhage
Lowers O2 levels in blood kidneys release REF RBC production in bone marrow
Anemia
Reduction in blood O2 due to low levels of hemoglobin or poor RBC production
Causes: hemorrhage, dietary deficiency in iron
http://www.wisc-online.com/objects/index_tj.asp?objid=AP14604
White blood cells or WBC’s
Outnumbered by RBC’s
Have a nucleus
Types of WBC’s
a.) Granulocytes – small
cytoplasmic granules are
visible, when stained
Produced in bone marrow
b.) Agranulocytes – do not
have granular cytoplasm
Produced in bone marrow but
are modified in lymph nodes
Phagocytes Destroy invading microbes by
phagocytosis
Diapedesis – move like an amoeba
• Lysosomes release digestive enzymes
Digests microbe as well as itself
• Pus forms – fragments of WBC and invader
A colored scanning electron micrograph of a macrophage engulfing a parasite of the Leishmania genus. To defend the body, macrophages will surround a foreign invader, bring it inside the cell, then use enzymes to digest the material.
Types of Phagocytes:
a.) Neutrophils:
Toxins, hemorrhage, fever, burns
b.) Eosinophils:
Allergies and parasitic worms
c.) Basophils:
Damage to tissues
http://www.wisc-
online.com/objects/index_tj.asp?objid=AP1
4704
Other WBC’s form antibodies which interfere with invading microbes
Neutrophils are very active in phagocyting bacteria and are present in large amount in the pus of wounds.
12
Eosinophils attack parasites and phagocyte antigen-antibody complexes.
13
Basophil secrete anti-coagulant and vasodilatory substances as histamines and serotonin. Even if they have a phagocytory capability, their main function is secreting substances which mediate the hypersensitivity reaction.
14
The lymphocytes are the main constituents of the immune system which is a defense against the attack of pathogenic micro-organisms such as viruses, bacteria, fungi and protista. Lymphocytes yield antibodies and arrange them on their membrane.
15 Two types: B and T lymphocytes
Monocytes are the precursors of macrophages. After attaining maturity in the bone marrow, enter the blood circulation. Then they migrate into the connective tissue, where they become macrophages and move within the tissues. In the presence of an inflammation site, monocytes quickly migrate from the blood vessel and start an intense phagocytory activity.
16
A.k.a thrombocytes Do not contain a nucleus
Produced in bone marrow
Move through blood vessels and initiate blood clotting reactions
Prevent blood loss
Process:
Microbes cannot enter but WBC’s can
wraps around cut and seals it
converted into fibrin
splices fibrinogen
becomes thrombin
Ca 2+ and thromboplastin activates prothrombin
platelet breaks apart and
releases thrombo-plastin
Platelet strikes a
torn blood vessel
Thrombus – blocks a blood vessel
Types: Coronary
Cerebral – stroke
If a blood clot moves or dislodges, it becomes an embolus Types of embolisms:
Pulmonary, coronary, cerebral
http://www.nucleusinc.com/medical-animations.php?page_no=3&show_anim=dvt.swf
Hemophilia
An inherited defect in the clotting process
Fluosol
Allows one to avoid blood transfusions
Provides a 5 day temporary period in which one’s bone
marrow may replenish RBCs
Contains fluorine
Requires no blood matching
May be frozen for long periods of time
Does not carry human viruses
Does not initiate blood clotting nor provide immunity
May be provided to patients who undergo multiple transfusions, due to disease
Read Section 11.1 in your textbook – Pages 348-353
Complete Section 11.1 Questions – Page 356 #’s 1, 3, 5-
7, 10-18
Blood micro-viewer activity
Fill in any unlabeled boxes for blood diagrams in your
workbook
Experiments with blood transfusions, the transfer of
blood or blood components into a person's blood
stream, have been carried out for hundreds of years.
Many patients have died and it was not until 1901,
when the Austrian Karl Landsteiner discovered
human blood groups, that blood transfusions became
safer.
Mixing blood from two individuals can lead to blood
clumping or agglutination. This can have fatal
consequences. Karl Landsteiner discovered that
blood clumping was an immunological reaction which
occurs when the receiver of a blood transfusion has
antibodies against the donor blood cells.
Karl Landsteiner's work made it possible to determine
blood types and thus paved the way for blood
transfusions to be carried out safely. For this
discovery he was awarded the Nobel Prize in
Physiology or Medicine in 1930.
IMPORTANT TERMS
Antigen
Molecules that cause the
synthesis of antibodies
when injected into another
organism
Antibody
Proteins found in blood that
attack and neutralize
substances that are foreign
to the body
The differences in human blood are due to the presence or
absence of certain protein molecules called antigens
(agglutinogens) and antibodies (agglutinins). The antigens are
located on the surface of the red blood cells and the
antibodies are in the blood plasma.
Individuals have different types and combinations of these
molecules. The blood group you belong to depends on what
you have inherited from your parents.
According to the AB0 blood typing system there
are four different kinds of blood types: A, B, AB
or 0
Blood group A
If you belong to the blood group A, you have A
antigens on the surface of your red blood cells
and B antibodies in your blood plasma.
Blood group B
If you belong to the blood group B, you have B
antigens on the surface of your red blood cells
and A antibodies in your blood plasma.
Blood group AB
If you belong to the blood group AB, you
have both A and B antigens on the surface
of your red blood cells and no A or B
antibodies at all in your blood plasma.
Blood group 0
If you belong to the blood group 0, you
have neither A or B antigens on the surface
of your red blood cells but you have both A
and B antibodies in your blood plasma.
ABO BLOOD TYPE SUMMARY:
AGGLUTINATION REACTION
According to above blood grouping systems, you can belong to
either of following 8 blood groups:
A Rh+
(34%)
B Rh+
(9%)
AB Rh+
(3%)
0 Rh+
(38%)
A Rh-
(6%)
B Rh-
(2%)
AB Rh-
(1%)
0 Rh-
(7%)
1. You mix the blood with three different reagents including either of the
three different antibodies, A, B or Rh antibodies.
2. Then you take a look at what has happened. In which mixtures has
agglutination occurred? The agglutination indicates that the blood has
reacted with a certain antibody and therefore is not compatible with blood
containing that kind of antibody. If the blood does not agglutinate, it
indicates that the blood does not have the antigens binding the special
antibody in the reagent.
3.If you know which antigens are in the person's blood, it's easy to figure out
which blood group he or she belongs to!
http://nobelprize.org/medicine/educational/
landsteiner/index.html
Try your luck with the Blood typing game!!!
People with blood group 0 are called "universal donors" and people with
blood group AB are called "universal receivers."
Universal Donors!
Universal Recipients!
Many people also have a so called Rh factor on the red blood
cell's surface.
This is also an antigen and those who have it are called Rh+.
Those who haven't are called Rh-. A person with Rh- blood does
not have Rh antibodies naturally in the blood plasma. But a
person with Rh- blood can develop Rh antibodies in the blood
plasma if he or she receives blood from a person with Rh+
blood, whose Rh antigens can trigger the production of Rh
antibodies. A person with Rh+ blood can receive blood from a
person with Rh- blood without any problems.
First studied in rhesus monkeys
Types
Rh positive: Have these antigens present on surface of RBCs
Rh negative: Do not have these antigens present
Hemolytic disease of the newborn (HDN)
Mother produces anti-Rh antibodies that cross placenta and cause agglutination and hemolysis of fetal RBCs
ERYTHROBLASTOSIS FETALIS
Type and crossmatch
Blood typing determines the ABO
and Rh blood groups of a blood
sample. A crossmatch tests for
agglutination reactions between
donor and recipient blood
•Complete blood count……The complete blood count
consists of the following: red blood cell count,
hemoglobin measurement (grams of hemoglobin per
100mL of blood), hematocrit measurement (percent
volume of red blood cells), and white blood cell count
Differential White blood count
It determines the percentage of
each type of white blood cell
Clotting
Platelet count and prothrombin
time measures the ability of the
blood to clot
•Blood chemistry….The composition of materials
dissolved or suspended in plasma (e.g. glucose, urea,
nitrogen, bilirubin and cholesterol) can be used to
assess the functioning and status of the body’s
system
A B AB O
A
B
AB
O
DO
NA
R
RECIPIENT
BLOOD COMPATIBILITY CHART:
= ANTIGEN of donor = ANTIBODY of recipient
Read Pages 354-355 in textbook
Complete Section 11.1 Questions – Page 356
#’s 1, 3, 5-7, 10-18
Blood micro-viewer activity
Fill in any unlabeled boxes for blood diagrams
in your workbook
11.2 THE BODY’S LINE OF DEFENSE
PAGES 357 - 366
Biology 20 Unit D
11.2 THE BODY’S LINE OF DEFENCE
Pathogen: an organism causing disease
An infectious disease may be caused by:
Viruses, bacteria, fungi, protozoa, flatworms and
roundworms
Staphylococcus aureus can be pathogen in the right conditions on the surface of the
skin (causing impetigo and other skin conditions)
Parasites Malaria: Single-
celled protozoan
parasites of the
genus Plasmodium.
Four species infect
humans by entering
the bloodstream.
Head Lice
(adult stage)
Giardia: a fungi that
infects the intestines of
animals causing
“beaver fever”. People
most often get it from
drinking contaminated
water
TAPEWORMS, RINGWORMS, AND OTHER PATHOGENS
VIRUSES
Influenza Virus (Flu)
Human Immunodeficiency
Virus (AIDS)
BACTERIA
Salmonella typhimurium
(Food Poisoning)
Syphilis- is an infectious venereal disease
caused by the spirochete Treponema
pallidum
Elephantitis
I.) FIRST LINE OF DEFENCE: NONSPECIFIC AND EXTERNAL (P357)
Skin – protective
Acidic secretions (pH of 3 – 5)
Respiratory tract (windpipe) – mucus
and cilia sweep foreign material away
from lung
Stomach – acids and protein
digesting enzymes destroy microbes
Tears, saliva, mucous secretions –
lysozyme (enzyme) destroys bacterial
cell walls
II.) SECOND LINE OF DEFENCE – NONSPECIFIC AND INTERNAL (P357)
A. Phagocytes (WBC’s) destroy microbes
TYPES OF PHAGOCYTES
Phagocytosis Ingestion of invading microbes
by certain WBCs
Pus - remaining fragments of protein, dead WBCs,
digested invader
B. INFLAMMATORY RESPONSE
Tissue damage due to physical injury Initiates an inflammatory
response
Nonspecific response that results in swelling, heat, and pain
Clues to second line of defence:
Pus
Inflammation
Neutrophils and macrophages
digest invaders
Release chemicals
Reach hypothalamus
Reset body temperature
to about 40OC
Fever makes it difficult for
harmful bacteria to survive
Fevers 40OC can be unsafe
Enzymes start to denature
D. PROTECTIVE PROTEINS
- prevent multiplication of bacteria and viruses
i) complement active against bacteria
once activated, some complements form pores in
bacterial cell walls and membranes
pores allow salts and fluids to enter bacterial cell
bacterium expands until it bursts
E. INTERFERON
active against viruses
tissue cells infected by viruses
produce and secrete interferon
chemical binds to uninfected cells
these cells now produce
substances that interfere with viral
replication
slower, but more specific
white blood cells and lymph system are involved
WBC respond to antigens: any substance recognized as foreign to the body
often antigens are part of a bacterial cell wall, viral coat, or foreign cell membrane
CELLS OF THE IMMUNE SYSTEM OVERVIEW:
BONE MARROW
RBCStay and Mature
WBC
AGRANULAR: GRANULAR
1. Monocytes:-mature into macrophages
2. Lymphocytes
1. Basophils
2. Neutrophils
3. Eosinophils
mature in Thymus Gland
mature in Bone Marrow
T- cells B - cells
migrate to lymph nodes and spleen
circulate in blood and lymph
Called antibody mediated
immunity: antibodies move
thru blood and lymph
called cell-mediated immunity:
cells move thru blood and lymph
Immune system detects an antigen
T-cells multiply which attack
the invader directly
B-cells multiply which
produce antibodies
target: bacteria,
viruses, etc. that have toxins infected
host cells; cancer cells, implanted
tissues
target: free bacteria,
viruses, and in body fluids
1. CELL-MEDIATED IMMUNITY
a macrophage engulfs a bacterium, then the bacterial antigen, along with an identification protein, will be displayed on the macrophage membrane
appropriate T-cell and its receptor is presented with the antigen, and is now activated
T-cell then grows and divides into the following:
a) Helper T-cell
directly stimulates a B-cell by presenting an antigen to it
b) Killer T-cell
release a chemical which forms a pore in foreign cell membrane bearing an antigen; cell swells and bursts
c) Suppressor T-cells
number increases slowly
suppress immune response
d) Memory T-cells
recognizes original invading antigen; can last a life-time
lymphokines: chemicals which stimulate immune cells to divide
2. ANTIBODY-MEDIATED IMMUNITY
B-cells produce antibodies: proteins which combine with and inactivate antigens
antigen binds to membrane-bound
antibody on B-cell
many plasma cells
which produce and
release antibodies
into blood and lymph
memory B-cells that remain in
bloodstream
antibody level increases,
and antigens disappear from body
B-cell divides into:
SUMMARY OF 3RD LINE OF DEFENCE
KILLER T-CELLS (CYTOTOXIC T CELL) DESTROY INFECTED HOST CELLS…KILL THE VIRUS WHERE IT’S MADE!
http://bcs.whfreeman.com/thelifewire/content/chp18/1
802004.html
http://highered.mcgraw-
hill.com/olc/dl/120110/micro33.swf
TASKS TO BE COMPLETED:
Read section 11.2 in your Textbook –
Pages 357-366
Section 11.2 Questions: 4, 6-8
Case Study: Bovine Spongiform
Encephalopathy (BSE) – Pages 361-363,
Questions 1-12.
Label the diagrams in the workbook
Biology 20 Unit D
Directions: READ Section 11.3 In the
TEXTBOOK and complete your own notes using
the following slides as a guide.
Section 11.3: Malfunctions of the
Immune System – Pages 367-370
11.3 MALFUNCTIONS OF THE IMMUNE SYSTEM
Can cause two types of problems:
1. Immunodeficiency diseases
Caused by: Virus (HIV)
Hereditary condition (severe combined immunodeficiency) SCID
Gene mutation
Inability to produce T and B cells
Exposure to cancer therapy or use of anti – inflammatory
drugs
1. Inappropriate attacks of immune system against non – threatening agents
Allergies
Autoimmune disorders
I.) ALLERGIES
Immune system mistakes harmless cells as harmful
Symptoms:
Tissue swelling
Mucus secretion
Constricted air passages
Severe allergic reactions may cause anaphylactic reactions
Hives, itching, swelling
Cells that “believe” they are in danger release bradykinin Stimulates release of histamine
Produced by basophils (WBCs) and mast cells
•Increases permeability of cells of capillaries
Causes reddening
•PROTEINS AND WBCS LEAVE CAPILLARY IN SEARCH OF MICROBE
•Hypertonic, thus, water follows by diffusion
Reactions may be brought on by:
Medications, vaccines, foods
Anaphylactic shock can occur quickly
Weakness, sweating, difficulty breathing
Nausea, diarrhoea, drop in blood pressure
Treatments or prevention:
Antihistamines
Medical alert bracelet or necklace
Read labels
II.) AUTOIMMUNE DISORDERS
Immune system mistakenly attacks own cells of body
Renegade lymphocytes treat body’s cells as foreign and attack own body’s cells
Usually held in check
Mutated T and B cells
Theory: suppressors secrete a substance that tells macrophage to engulf renegade cells
Failure of suppressor T cells to control renegade lymphocytes
Rheumatoid arthritis
Against connective tissue of joints
Rheumatic fever
Scars heart muscle
Type I diabetes
Against insulin – producing cells of pancreas
Lupus
Accumulation of antigen – antibody complexes that build up on walls of blood vessels, kidneys, joints, and skin
Multiple sclerosis
Against myelin sheath of nerve cells
III.) ORGAN TRANSPLANT REJECTION Main challenge is immune system’s ability to
distinguish “self” from “nonself”
Donor organ is identified by distinctive protein markers on its cell membranes
Major histocompatability complex (MHC)
Unique to each individual
Organ recipient makes antibodies designed to destroy foreign invader
Attempts are made to match MHC of the tissues of donors and recipients as closely as possible
Close relatives
Recently deceased donors
To reduce rejection, immunosuppressant drugs are administered
Also reduces immune system’s ability to fight off invading microbes
Place patients at risk for infections
ORGAN TRANSPLANTS IN ALBERTA
Alberta’s Capital Health Regional Transplant Program
At the U of A Hospital and Stollery Children’s Hospital
HOPE (human organ procurement and exchange)
Coordination, recovery, and distribution of organs in Alberta
Tissues include: eyes (cornea and sclera), skin, heart valves, and bone
IV.) STEM CELL RESEARCH
Stem cells
Are pluripotent
Can give rise to different types of body cells
Can replace pancreatic islet cells that have been damaged
Can repair damaged cartilage or cardiac tissue
Exist in adult skin stems cells as multipotent stem cells
Can be directed to become neurons or muscle cells
Weakening of suppressor T cells:
Drugs or serious infections
Decline with age
Some people are born with defective suppressor T cells
Treatment
Immune suppressing drugs
Reduce intensity of renegade cells
Autoimmune disease
Immune system mistakenly attacks own cells of body
Mutated T and B cells
Failure of suppressor T cells
Attempts are made to match MHC of the tissues of donors and recipients as closely as possible
Close relatives
Recently deceased donors
To reduce rejection, immunosuppressant drugs are administered
Also reduces immune system’s ability to fight off invading microbes
Place patients at risk for infections
TASKS TO BE COMPLETED:
Read Section 11.3 in the Textbook- Pages 367-
370
Complete your own notes for this section
Complete Section 11.3 Questions: Page 370 #1,
4, 6
Prepare for Unit Exam:
Read over your notes! Highlight the key ideas!
Complete the fill in the blanks review for chapter
10-11 in your workbook
Try the Chapter 11 Review Questions: Page 374 # 1-
16