Chapter 11 Blood and Immune System notes

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Transcript Chapter 11 Blood and Immune System notes

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
•Antibodies, immunity
(immunoglobulins)
•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


White blood cells or WBC’s

Outnumbered by RBC’s

Have a nucleus
 Types of WBC’s
a.) Granulocytes
b) Agranulocytes
Why You Are Still Alive https://www.youtube.com/watch?v=zQGOcOUB
i6s
c) 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
Phagocytosis http://faculty.ccbcmd.edu/~gkaiser/biotutori
als/eustruct/images/phagocyt.gif
http://highered.mheducation.com/sites/007
2495855/student_view0/chapter2/animatio
n__phagocytosis.html
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.wisconline.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.
11
 Eosinophils
attack
parasites and
phagocyte antigenantibody complexes.
12
 Basophil
secrete anticoagulant 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.
13
 The
lymphocytes are the
main constituents of the
immune system which is a
defense against the attack
of pathogenic microorganisms such as viruses,
bacteria, fungi and
protista. Lymphocytes
yield antibodies and
arrange them on their
membrane.
Two types: B and T lymphocytes
14
 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.
15
thrombocytes

A.k.a

Do not contain a nucleus

Produced in bone marrow

Move through blood vessels and initiate blood clotting reactions


Prevent blood loss
Process:
platelet
Platelet
breaks
2+ and
Ca
strikes a
apart
thromboplastin
becomes
and
torn
thrombin
activates
releases
blood
prothrombin
thrombo
vessel
-plastin cannot enter but WBC’s can
 Microbes
splices
fibrinogen
converted
into fibrin
wraps
around
cut and
seals it

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
Hemophilia
 An inherited defect in the clotting process



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!
Try your luck with the Blood typing game!!!
http://nobelprize.org/medicine/educational/
landsteiner/index.html
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
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
Head Lice
(adult stage)
Malaria: Singlecelled protozoan
parasites of the
genus Plasmodium.
Four species infect
humans by entering
the bloodstream.
Giardia: a fungi that
infects the intestines of
animals causing
“beaver fever”. People
most often get it from
drinking contaminated
water
TAPEWORMS,
PATHOGENS
RINGWORMS, AND OTHER
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
I.) FIRST LINE
OF
DEFENCE:
NONSPECIFIC AND EXTERNAL
 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
(P357)
II.) SECOND LINE OF DEFENCE
– NONSPECIFIC AND INTERNAL (P357)
A. Phagocytes (WBC’s) destroy microbes
T YPES 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

i)
- prevent multiplication of bacteria and
viruses
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
RBC
Stay and Mature
WBC
GRANULAR
AGRANULAR:
1. Basophils
1. Monocytes:
-mature into
macrophages
2. Neutrophils
2. Lymphocytes
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
Immune system detects an antigen
T-cells multiply which attack
the invader directly
called cell-mediated immunity:
cells move thru blood and lymph
target: bacteria,
viruses, etc. that have toxins infected
host cells; cancer cells, implanted
tissues
B-cells multiply which
produce antibodies
Called antibody mediated
immunity: antibodies move
thru blood and lymph
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:
to divide
chemicals which stimulate immune cells
2.
ANTIBODY-MEDIATED IMMUNITY
 B-cells produce antibodies: proteins which combine with
and inactivate antigens
antigen binds to membrane-bound
antibody on B-cell
B-cell divides into:
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
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.mcgrawhill.com/olc/dl/120110/micro33.swf
Biology 20 Unit D
Section 11.3: Malfunctions of the
Immune System – Pages 367-370
Directions: READ Section 11.3 In the
TEXTBOOK and complete your own notes using
the following slides as a guide.
11.3 MALFUNCTIONS

1.
OF THE
IMMUNE SYSTEM
Can cause two types of problems:
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