Download BIOLOGY 12 - CHAPTER 11 - BLOOD

BIOLOGY 12 - CHAPTER 11 - BLOOD - CHAPTER NOTES
Facts
• Human beings are approximately 70% WATER by body weight.
o Most of this water is within cells, while a smaller amount is found within:
o Tissue fluid (surrounds cells)
o Lymph (within lymph vessels)
o Blood vessels (in our blood)
Functions of Blood (an average person has ≈ 5 to 6 liters of blood)
• seals injuries by flotting
• maintain homeostasis
• fights infections
• is a liquid connective tissue.
• transports gases, wastes, and
nutrients
Questions (p. 227)
1) What are the two main components of blood? plasma and the formed elements
2) What are the 3 types of formed elements? Red blood cells, white blood cells and
platelets
3) Describe plasma. Makes up 55% of blood volume.
Organic and inorganic substances (proteins, gases, salts, nutrients,
wastes).dissolved or suspended in water.
Plasma
Fill in the missing information on the table below
Plasma Constituent
Water
Function
Maintains blood volume and
transports molecules
Source
Absorbed from large
intestine
Plasma Proteins
All maintain blood osmotic pressure & pH
Liver
a. Albumin
b. Fibrinogen
c. Globulins
Gases
a. Oxygen
b. CO2
Nutrients: Fats, glucose,
amino acids, etc.
Maintain blood volume and pressure
Clotting
Transport; fight Infection
Cellular Respiration
End product of metabolism
Food for cells
Lungs
Tissues
Absorbed from
intestinal villi
Salts
Maintain blood osmotic pressure/pH, aid
metabolism
Absorbed from
intestinal villi
Excretion by kidneys
Liver
Aid metabolism
Varied
Nitrogenous waste
Urea
Uric acid
Hormones, vitamins etc.
Blood- Page 1 of 10
Formed Elements: the "solid part" of blood
Formed Element
Red blood cell
(over 95% of formed
elements)
AKA
Erythrocytes
Function
Source
Red
bone
marrow
Transport O2 and
help transport CO2
White blood cell
(granular /agranular)
Leukocytes
Fight infection
Red bone marrow
and lymph tissue
Platelets
Thrombocytes
Aid clotting
Red bone marrow
Identify and Label
Erythrocytes
Platelets
Granular
Leucocytes
Agranular
Leucocytes
Blood Proteins
• Are required for the transport of many molecules.
• E.g. Cholesterol is a lipid (non-polar) is insoluble in plasma (polar). ∴ carried by proteins.
• HDL (high-density lipoprotein) is “better” than LDL for binding with cholesterol,
according to some studies, in the prevention of atherosclerosis.
• Blood proteins also contribute to the viscosity of blood (“blood is thicker than water”),
which aids in transport.
• Blood proteins also contribute to osmotic pressure, which maintains blood volume.
8.2 BCNotes - Blood - Teacher - Page 2 of 10
Hemoglobin (p. 228) transporter of O2
• Hemoglbin(Hb) is made of 4 polypeptides (2 alpha (α) and 2 beta (β)).
• Each polypeptide has an iron-containing heme group which attaches to
oxygen
• Hb weakly binds with O2 in the cool, neutral conditions (lungs), and
easily gives up O2 in the warmer and more acidic tissues.
• Hb is contained within red blood cells.
• Hb is a red pigment, red blood cells appear red (When O2 is attached).
• OXYHEMOGLOBIN (Hb bound to oxygen, abbreviated as HbO2) is bright red, while
REDUCED HEMOGLOBIN (hemoglobin that has lost its oxygen) is dark purple.
• Carbon Monoxide (CO) is a poison found in car exhaust. CO binds better than O2 to Hb
• CO stays bound for several hours to Hb,regardless of the environmental conditions. CO
poisoning can lead to death because O2 cannot be transported.
• Hemoglobin picks O2 up in the lungs and releases O2 in tissues. Meanwhile, CO2 and
wastes diffuse out of cells.
Exchange at the Capillaries
•
•
•
•
•
•
•
•
Recall: Blood pressure (BP) is
greatest in arteries and
decreases in the vessels as it
moves away form the heart.
BP is a force (push) against
the walls of the blood vessels
Osmotic pressure (OP) is the
force from the fluid between
cells and the blood vessels.
At the arterial side of a
capillary, BP > OP and
therefore water, oxygen and glucose tend to leave the bloodstream (small molecules).
At the venous end of a capillary, the OP > BP and, therefore, water, ammonia, and
carbon dioxide tend to enter the bloodstream (small molecules).
Somewhere in the middle BP is equal to OP. At this point small molecules move in and
out by diffusion.
Net pressure is the difference between BP and OP.
Reduced hemoglobin can pick up some CO2 to form carbaminohemoglobin (HbCO2) but
most CO2 combines with water to form carbonic acid which then dissociates to form the
bicarbonate ion (HCO3-),
CO2 + H2O <--->H2CO3<--->H+ + HCO3the enzyme carbonic anhydrase
speeds up this reaction.
•
dissociation
How most CO2 is
transported
H+ form the above reaction is picked up by the globin portion of hemoglobin to become
HHb thus pH is maintained (homeostasis).
8.2 BCNotes - Blood - Teacher - Page 3 of 10
T
Red Blood Cells (p.228)
• There are close to 30 trillion blood cells in an adult.
• Each mm3 of blood contains from 4 1/2 to 5 1/2 million red
blood cells and an average total of 7,500 white blood cells.
• In humans, red blood cells are small, biconcave, disk-shaped
cells without nuclei.
• Red blood cells are made by cells called “STEM CELLS” in
red bone marrow (over 2 million per second!) of the skull, ribs, vertebrae, and ends of
the long bones. Here, Stem Cells continuously divide. During the maturation process, a
red blood cell loses its nucleus and gets much smaller.
• Oxygen levels in blood determine the rate of RBC formation.
o If O2 is low, the kidneys produce renal erythropoietic factor (REF) REF
combines with globulin from the liver bone marrow produces more RBC.
• RBC live for 120 days then destroyed in the liver and spleen. The iron is recovered
from the hemoglobin and sent to the bones, while the heme portion is chemically
degraded and is excreted by the liver in the bile (disgestive function) as bile pigments.
White Blood Cells (p. 229))
• White blood cells (WBC aka leukocytes) are usually larger than RBC (8 - 20 µm), have a
nucleus, and appear white (if not stained -- when stained, they appear bluish).
• Number comparison: 600 RBC: 1WBC (leukocytes).
Two main types of Leukocytes:
1) Granulocytes: have granules (or grains) in the cytoplasm and a multi-lobed nucleus
joined by nuclear threads (called "polymorphonuclear"). The granulocytes include:
a) Neutrophils (phagocytizes primarily bacteria),
b) Eosinophils (phagocytizes and destroys antigen-antibody complexes)
c) Basophils (congregates in tissues, releases histamine when stimulated). Formed in
the red bone marrow. The granules of a neutrophil are lysosomes.
2) Agranulocytes (no granules): Include Lymphocytes and Monocytes. Have a circular
(lymphocytes) or indented (monocytes) nucleus. Lymphocytes are produced in lymphoid
tissue found in the spleen, lymph nodes, and tonsils.
a) Type B lymphocytes produce antibodies in blood and lymph,
b) Type T lymphocytes kill virus-containing cells.
c) Monocytes become macrophages.
WBC Functioning
• Fight infection, develop immunity and fight disease
• Neutrophils (≈ 60 - 70% of WBC) lymphocytes (≈ 25 to 30%) main contributors to
fighting infection
• Phagocytic (engulf invaders at infection site) WBC’s: neutrophils, monocytes, and
eosinophils are
• Lymphocytes secrete a type of gamma globulins (proteins) called immunoglobulin
(antibodies). Antibodies combine with foreign substances to inactivate them.
• Lymphocytes (smallest WBC). When microbes invade the body, lymphocytes begin to
multiply and they become transformed plasma cells.
° Specific microbe results in a specific type of plasma cell.
° This plasma cell produces a specific antibody to destroy the particular microbe.
8.2 BCNotes - Blood - Teacher - Page 4 of 10
•
•
•
•
Red bone marrow continually produces WBC’s except lymphocytes and monocytes
(produced when needed)
When a parasite or virus invades and begins to colonize, the reserves of white blood cells
are released and the production of large quantities of the appropriate white cells begins.
It is this increased production that causes fever.
WBC’s are very specific for various illnesses, their count can help doctors diagnose
patients.
Blood Clotting (p.230)
• After an injury, coagulation "or clotting" takes place to prevent excessive blood loss.
• This requires the action of 1) platelets 2) prothrombin, and 3) fibrinogen.
• Megakaryocytes fragment to become platelets (thrombocytes).
• Fibrinogen and prothrombin are plasma proteins produced by the liver (vitamin K is
needed for the production of prothrombin)
Steps involved in clot formation:
1.Platelets clump at the
site of the puncture and
partially seal the leak
2. Platelets and injured tissues
I n j u r e d t i s s u e s a n d p l a t e le t s
release
r e l e a s e Pthe
r o t henzyme
o m b i n A prothrombin
c ti v a to r
( a n e n z y m e ) ( v i ta m i n K r e q u i r e d
activator
f o r th e p r o d u c t i o n o f P r o t h o m b i n )
P r o th r o m b i n A c ti v a to r
3. Prothrombin
activator converts
c a t a ly z e s t h e c o n v e r s i o n o f
+2
P r o to
t h r thrombin.
o m b in t o T hCa
ro m b in.
prothrombin
(Ca
i s n e c e ss a r y f o r t h i s s t e p )
needed
++
P ro t h ro m b in
A c t iv a t o r
+ C a+
+
Th rom bin
P r o t h ro m b in
T h r o m b in i s a n e n z y m e t h a t
a c ts l ik e a p a ir o f s c i s s o r s ,
c u t ti n g s h o r t a m i n o a c i d
e n d s o f f F ib r i n o g e n
m o lec u les
F i b r in o g e n
F i b r in F r a g m e n t
4. Thrombin acts as an
enzyme and cuts two short
a.a. chains from each
fibrinogen molecule.
5. Fibrinogen fragments join end
to end to form long fibers of fibrin.
F i b r i n F r a g m e n ts j o i n t o g e t h e r
6. Fibrin
e n d threads
to e n d t o join
f o r m together
l o n g f i b e r sand
.
F ib r i n f ib e r s f o r m th e
form the fframework
of
the
clot.
ra m e w o rk o f t h e clo t .
RBC’s and platelets gets trapped and
contribute to the clot
Other Clotting Facts
• RBC’s trapped in the clot give it its red colour.
8.2 BCNotes - Blood - Teacher - Page 5 of 10
•
•
•
•
Clotting takes place faster at warmer temperatures than cold. Why? because clotting is
controlled by enzymes which work better at warmer temperatures.
Serum is plasma from which the fibrinogen has been removed due to clotting.
Once blood vessels are healed, plasmin (an enzyme) breaks down the fibrin network
and restores the fluidity of plasma.
Haemophilia – a genetic disorder. Persons do not produce a necessary clotting protein.
Clotting proteins can be produced using recombinant DNA
Infection Fighting: another major function of blood
• The skin - body's first line of defense against invading pathogens like bacteria and
viruses - major burn victims may die because of infection that follows not the burn itself
• The blood - The second line of defense: white blood cells and gamma globulins.
Antibodies (p.246)
STRUCTURE OF A' A'TIBODY
• Antibodies are very specific proteins that attach
to invading pathogens
• Lymphocytes produce antibodies in response
Light chain
to invading pathogens.
Variable Region
• Each lymphocyte produces only one type of
antibody that is specific for one type of antigen.
Constant Region
Heavy Chain
• An antigen is a foreign substance (usually a
protein, sometimes a carbohydrate)
• an antigen could be protein coat of a virus
• antigens stimulates the release of antibodies
Antibodies binding to
antigens (proteins on
• Antibodies bind with antigens causing antigens
surface of a cell)
to become harmless.
• An antibody fits a specific antigen like a lock
and key.
• An individual is immune to an antigen if he/she has antibodies to that particular antigens.
• The blood in the individual contains lymphocytes that can remain in the system for years,
ready to produce antibodies if that antigen is detected.
• Exposure to the antigen (naturally or by vaccine) can cause active immunity to develop.
• Diseases will often cause an increase in a particular type of white cell. e.g.
mononucleosis characterized by greater #'s of dark staining lymphocytes. Leukemia is a
form of cancer characterized by uncontrolled production of abnormal white cells, which
accumulate in the bone marrow, lymph nodes, spleen, and liver, causing them to
malfunction. Leukemia patients often have severe anemia, clotting difficulties, and
succumb to many infections.
The Inflammatory Reaction p.242-243
Whenever the skin is broken due to a minor injury, a series of events occur that are known
as the inflammatory response because there is swelling and reddening at the site of the
injury. This response is designed to get the body's defenses assembled as quickly as
possible at the site where they are needed.
Steps in the Immune Response
Injure
d tissues
a nd
c apillaand
ries
1. Injured
blood
vessels
re lease
fa ctors
t for m precursors
tissue
cells tha
release
B RADY
KI'I'.
of bradykinin
8.2 BCNotes - Blood - Teacher - Page 6 of 10
B ra dykinin:
2. Bradykinin
2. Bradykinin
• initiates nerve impulses PAIN
• causes mast cells to release histamine,
Fact: Mast cells are a type of
cell that resides in tissues that
are derived from Basophils
3. Histamine causes redness,
localized heat and capillaries to
dilate and enlargen
4. Enlarged capillaries
increase permeability
allowing proteins and fluids
to escape swelling.
5. Lymphocytes release
antibodies that attack any
invading pathogens
(remember, bacteria are
everywhere), preparing
them for phagocytosis by
neutrophils or monocytes.
6. Monocytes become
macrophages (p.229)
Macrophages are large
phagocytic cells (5 to 10 X
larger than monocytes) that
are able to devour a hundred
invaders and still survive.
Bacteria
BLOOD TYPING p. 254-255
8.2 BCNotes - Blood - Teacher - Page 7 of 10
ABO Grouping.
• 4 possibile blood types:
i.
type A
ii.
type B
iii.
type AB
iv.
type O
• These blood types are due to 2 antigens (A or B) that may be present on the surface of
the RBC’s. Plasma of individuals also contain antibodies to the antigens they are
lacking.
•
•
If the same antigen and antibody are present, agglutination (or clumping) of red cells will
occur (may cause death).
Blood recipients may only receive donated blood for which they have no antibodies in
their plasma.
Fill in table with this last point in mind
Blood Type
Can receive a blood transfusion
from what blood types?
Cannot receive a blood transfusion
from what blood types?
A
A or O
B
B or O
AB
All 4 types
O
O
B or AB
A or AB
----------
A, B or AB
Question: Explain why people with “O” type blood are termed universal donors, yet are
limited in the blood they can receive. (2 marks)
•
•
blood type O is accepted by all blood types therefore it is the universal donor
blood type O can only receive blood type O because it produces anti-A and anti-B
antibobodies
The Rh System
Another important antigen in matching blood types is the Rh factor (another antigen found on red blood cells)
8.2 BCNotes - Blood - Teacher - Page 8 of 10
•
•
•
•
People that have this antigen on
their RBC’s are termed Rh
positive; those without the
antigen are Rh negative.
If you are blood type AB from the
ABO system and do not have
the RH antigen you’re blood
type is ABTherefore there are 8 blood
types when the 2 systems are
combined
Rh individuals do not normally
make antibodies to the Rh
factor, unless they are exposed
to the Rh factor.
The Rh factor and Pregnancy.
• If the mother is Rh- and the
father is Rh+, the child may be
Rh+.
• During gestation, it is normal
that a few red cells from the
child will find their way into the
mother's system -- she will
then produce Rh antibodies.
• If the mother becomes
pregnant with another Rh
positive baby, Rh antibodies
may cross the placenta and
destroy the child's red cells.
This is called fetal
erythroblastosis (or hemolytic disease of the
newborn).
Antibody
Current treatment: prevent the mother from
producing Rh antibodies.
• How? give Rh- women an Rh immune globulin
injection (like an injection of antibodies) called
RhoGAM just after the birth of any Rh+ child.
This injection will destroy any RBC’s left over
from the baby, before the mother’s immune
sytem has a chance to start producing her own
antibodies.
• The injection won't work if the woman has
already started to produce her own antibodies.
Determining Blood Type
8.2 BCNotes - Blood - Teacher - Page 9 of 10
Recall: agglutination is the clumping of blood when an antibody that is specific to its
antigen combine. (e.g. combining antibody A and blood type A will agglutinate)
• Blood types can be determined by observing this change.
Example: The blood of 4 students was placed on separate slides with the the specified
antibodies.
• Square W is prepared with anti-A solution which causes agglutination in blood containing the A
antigen.
• Square X is prepared with anti-B solution which causes agglutination in blood containing the B
antigen.
• Square Y is prepared with anti-Rh solution which causes agglutination in blood containing the Rh
antigen. Blood which contains the Rh antigen is said to be Rh+, while blood without the Rh antigen
is said to be Rh-.
• Square Z is a control (no solutions added).
What conclusion can be made about each student from the above observations?
• Student 1 is Blood type O• Student 2 is Blood type A
• Student 3 made a mistake control should not have antibodies agglutination
should not have occurred
• Student 4 is Blood type AB+
8.2 BCNotes - Blood - Teacher - Page 10 of 10