Blood and Immunity Flashcards
What is blood?
A fluid tissue
Why is blood important?
For the protection and survival of all of our bodies cells
How much blood does the average person have?
5L
What percentage of blood is plasma?
55%
What is plasma?
Mainly water; transports dissolved O2, CO2, nutrients, waste, salts, hormones, and vitamins
What percentage of blood os WBC’s and platelets?
<1%
What percentage of blood are RBC’s?
45%
What are RBC’s
Erythrocytes; have no nucleus; big
What are WBC’s?
Leukocytes; have a nucleus; biggest
What are platelets?
Thrombocytes; have no nucleus; tiny
What can separate the two components of blood?
A centrifuge
What is a centrifuge?
An apparatus that spins blood in test tubes forcing the solid particles to the bottom and the plasma to the top; this mechanical separation allows us to separate and use various blood products
What does blood help maintain?
Homeostasis
How does blood do this?
- Transports O2 and CO2 (RBC and plasma)
- Transports salts and minerals (plasma)
- Clotting (platelets)
- Maintaining pH (plasma)
- Infection fighting (WBC)
- Maintaining temperature (plasma)
- Maintaining water balance (plasma)
What are the three main functions of blood?
Transport, clotting, and infection fighting
What does blood carry from the lungs to the tissues?
Oxygen
What does blood carry from the tissues to the lungs?
Carbon dioxide
What does the blood carry from the digestive tract to the tissues?
Absorbed nutrients
What does the blood carry from the tissues to the kidneys?
Waste for excretion
What blood components facilitate transport?
A. Blood proteins
B. RBC’s (erythrocytes)
What are three blood proteins?
- Albumin
- Fibrinogen
- Globulins
What does albumin do?
Transports bilirubin and regulates water balance
What does fibrinogen do?
Involved in clotting
What do globulins do?
Fight infection (immunoglobulins/antibodies), transport cholesterols
What do these proteins help do?
Maintain viscosity (thickness) of blood so it can flow; also help to create osmotic pressure and keep blood volume constant
What do RBC’s contain?
Special protein units called hemoglobin
What is hemoglobin made up of?
4 polypeptide chains (globin) and iron (heme)
What is the function of hemoglobin?
To carry oxygen (no nucleus)
What has a higher affinity for hemoglobin than oxygen does?
CO
What does that mean?
CO can easily bind, causing carbon monoxide poisoning
How many molecules of hemoglobin are there in each RBC?
About 200 million
How many RBC’s are in 1mL of blood?
About 500 million
Where are RBC’s manufactured?
The bone marrow of the skull, ribs, vertebrae, and long bones
How long do RBC’s live for?
About 120 days
What happens after 120 days?
RBC’s are broken down by the liver and spleen
What happens to the iron from the hemoglobin?
It is recycled
What is the heme group used as?
A bile pigment
At high altitudes, oxygen levels are low, so what does the body increase?
The number of RBC’s
Why do athletes train at high altitudes?
To increase the number of RBC’s, so they can exchange more oxygen
What are three RBC disorders?
- Anemia
- Sickle Cell Anemia
- Pernicious Anemia
What is anemia?
A deficiency in the number of RBC’s, resulting from iron deficiency; symptoms include tiredness, feeling run down, and hair loss
What is sickle cell anemia?
A genetic disorder where the RBC’s are no longer donut shapes, but sickle shaped, because of this mutation, the RBC’s do not effectively transport oxygen, and they don’t flow as easily through the blood vessels
What is pernicious anemia?
Vitamin B12 is not absorbed from the intestines (B12 is necessary for RBC formation)
What’s the main thing that RBC’s transport?
Oxygen
What’s the main thing that plasma transports?
CO2
What is produced in cells as a by-product of cellular respiration?
CO2
Carbon dioxide can join to hemoglobin to produce what?
Carbaminohemoglobin
What is most carbon dioxide transported as?
With the help of water, HCO3-
What is the sequence for carbaminohemoglobin?
- CO2 + H2O
- H2CO3
- H+ + HCO3-
Where is H+ carried and what does it do?
Carried in the blood plasma and maintains the blood pH
What does HCO3- do?
Acts as a buffer in the blood
What is the pH of blood?
About 7.4
What type of reaction is blood clotting?
Cascade reaction
What must blood do if an injury occurs to prevent further blood loss?
Clot/coaggulate
What three substances does the clotting process require?
- Platelets
- Prothrombin
- Fibrinogen
What are platelets?
Specialized cell fragments, from megakaryocytes in the bone marrow, that do not contain a nucleus. They have jagged edges that help to initiate the blood clotting process
What is a prothrombin?
A protein involved with blood clotting that is made with the help of vitamin k, by the liver. This protein is converted to the enzyme thrombin, with the aid of calcium ions
What is fibrinogen?
A long chain protein, also made by the liver, with the help of the enzyme thrombin, fibrinogen is broken dow into smaller fragments that form threads called fibrin
What are the steps of the clotting process?
- Damaged platelets and tissue cells release thromboplastin (a prothrombin activator)
- Thromboplastin releases calcium ions to cause prothrombin to become the enzyme thrombin
- The enzyme thrombin causes fibrinogen to become fibrin, which is the key component of the clotting process
What does a clot consist of?
Platelets and blood cells tangled together in fibrin threads
What is the clotting process?
Enzymatic; can be sped up with increased temperatures
What happens once blood vessels repair?
Plasmin destroys the fibrin thread, and restores circulation
What is the remaining yellow liquid (blood plasma without fibrin) called?
Serum
What are three problems with blood clotting?
- Thrombus
- Embolus
- Hemophilia
What is a thrombus?
A blood clot that forms in a blood vessel, cutting off the blood flow, and oxygen supply
What is an embolus?
A blood clot that dislodges and is carried by the circulatory system to vital organs. If the clot stops, blocking blood vessels in the brain, this is called a cerebral embolism (stroke). If a clot blocks blood flow in the heart, this is called a coronary embolism (heart attack)
What is hemophilia?
An inherited clotting disorder, where a person lacks clotting factors. The blood does not clot appropriately without this clotting factor to initiate the process.
What are large complexes of carbohydrates and proteins found on the membranes of RBC’s?
Glycoproteins (ID cards/antigens)
What do these complexes act as?
Markers; recognized as being either friend or foe (foreign antigens) by cells that don’t have them
What will a person receiving blood or tissue containing foreign markers (antigen) develop?
Antibodies to that blood or tissue and reject it
What will this cause the blood to do?
Agglutinate (clump); clogging capillaries and preventing oxygen and nutrient exchange
What is this linked to?
An attack by your immune system
What blood types can type A accept and donate to?
Accept- A, O
Donate- A, AB
What blood types can type B accept and donate to?
Accept- B, O
Donate- B, AB
What blood types can type AB accept and donate to?
Accept- A, B, AB, O (universal recipient)
Donate- AB
What blood types can type O accept and donate to?
Accept- O
Donate- A, B, AB, O (universal donor)
What blood types can Rh+ accept and donate to?
Accept- Rh+, Rh-
Donate- Rh+
What blood types can Rh- accept and donate to?
Accept- Rh-
Donate- Rh-, Rh+
What is Rhesus factor (Rh)?
Another level of blood typing In adults
How many Canadians are Rh+?
About 85% of Canadians are Rh+, and have the Rh antigen
How many Canadians are Rh-?
About 15% are Rh- and don’t have the antigen.
When would antibodies to the rhesus factor be produced?
Only after a blood transfusion
What is the immune response to Rh?
In adults, the immune response is mild, but in children it can be fatal
What are the problems of a Rh- mother having an Rh+ child?
At the birth of a first Rh+ child, the mothers blood mixes with the baby’s and the mother will make antibodies to the Rh+ type. If a second Rh+ child is conceived, the mothers antibodies can cross the placental barrier causing the child’s blood to clump, and the baby to die
What is this condition called?
Erythroblastosis fetalis (blue baby syndrome)
How can blue baby syndrome be treated/prevented?
By either giving the mom a drug that inhibits the formation of antibodies against the Rh+ antigens, or by transfusing the baby with Rh- blood
How is blood type tested?
By exposing blood samples to Anti A, Anti B, and Anti Rh antibodies; if agglutination (clumping) occurs the person has the antigen on their RBC’s
What is the bodies first line of defence against infections?
Physical barriers
- Skin
- Mucous and cilia in respiratory tract
- Stomach acids to destroy invaders
- Lysozyme in tears
If the first line of defence fails, what is used?
The second line of defence
What occurs before the second line of defence?
You’ll have an inflammatory response
What is an inflammatory response?
Through the use of blood trying to flush the area and attack with non-specific macrophages
What is involved in the second line of defence?
- White blood cells (leukocytes)
- Lymphocytes
- Globulins
What do WBC’s do?
Engulf particles
What do lymphocytes do?
Produce antibodies
What are the two types of lymphocytes?
- T cells
2. B cells
What are T cells?
Stored in the thymus gland, identify invaders, and call B cells into action; cellular attack
What are B cells?
Made in the bone marrow and make antibodies to the antigens; humoral attack
What are globulins?
Complementary proteins that
1. form a border around the invader, sealing it in
2. Attach to the invader and dissolve the cell membrane
3. Attach to the invader and attract WBC’s
(antibodies=immunoglobulin)- y shape
What is the ratio of WBC to RBC?
700:1; far less numerous
What makes WBC’s distinguishable from RBC’s?
WBC’s contain a nucleus
How do some leukocytes destroy microbes?
Diapedesis
What is diapedesis?
When leukocytes squeeze out of capillaries and move toward the microbe like an amoeba, engulf the microbe, and release enzymes that digest the microbe and the leukocyte
What is the remaining substance of diapedesis called?
Puss
What do other leukocytes do?
Produce antibodies that interfere with the normal functioning of toxins or microbes
What are the two types of leukocytes?
Granulocytes and agranulocytes
What is an antigen?
The ID card that identifies a toxin, foreign material, bacteria, virus, or parasite
What are antibodies?
Y shaped proteins that combine with an antigen to make it more recognizable to macrophages (big cells that eat stuff), and cause agglutination (clumping of cells)
What kind of response involves making/using antibodies?
Immune specific response
What is immunity?
The exposure of a cell to an antigen, either naturally or injected in a vaccine, causing an immune response and antibodies to develop
What is the order of immunity?
- Macrophage
- Helper T cells
- B and T cells
- Suppressor T cells
- Memory T cells
What happens when a macrophage’s cell membrane is pressed into an antigen?
Helper T cells read the antigen’s shape and release a chemical messenger called lymphokine
What does lymphokine do?
Causes B cells to divide and produce antibodies
What else is activated by lymphokine and what do they do?
Killer T cells; activated to puncture the cell membrane of the invader, thus killing the invading cells. Also destroy mutated cells and potential cancerous cells
What happens once the infection is controlled?
Suppressor T cells signal the immune system to slow down.
Due to this most B and T cells will die off in a few days, however what remains and what does it do?
Special cells called memory T cells; they hold an imprint of the antigen, allowing your body to respond more quickly if a reoccurance should occur
What are mutated B and T cells called and what do they do?
Renegade cells; can turn on the organism, and start attacking its own cells (auto-immune disease)
Usually what holds renegade cells in check?
Suppressor T cells
However sometimes this can fail, what are some auto-immune diseases?
Rheumatic fever- causes attack and scarring of the heart tissue
Rheumatoid arthritis- an attack against the bones and connective tissue causing degeneration
What can weaken suppressor cells, increasing vulnerability?
Some drugs or serious infections
What are 4 immune disorders?
- Mononucleosis
- Leukemia
- AIDS
- Allergies
What is mononucleosis?
Excess number of lymphocytes caused by the Epstein-Barr virus
What is leukemia?
A form of cancer characterized by excessive uncontrolled production of high levels of poorly developed WBC’s
What is AIDS?
Acquired Immune Deficiency Syndrome; An infection caused by the HIV virus, and is characterized by an abnormally low number of leukocytes (specifically helper T cells) and a decreased amount of antibodies which results in unorganized attacks on other foreign invaders
What are allergies?
Occur when the body recognizes normally harmless protein substances as invaders, and the immune response is set into action
What are vaccinations?
Introducing dead or weakened microbes (infectious particles) into the body, the body responds by producing antibodies
How do vaccines work?
Virulent microbes cause the disease before providing immunity
What does an antibiotic do?
Interferes with the production of bacterial cell walls, causing the membranes to burst and the bacteria to die
What is the downside of antibiotics?
Micro-organisms have the ability to mutate and become immune to antibiotics, so they become less effective if overused
What does not respond to antibiotics?
Viruses
How long will it take for a viral infection will clear up with antibiotics?
2 weeks with, 2 weeks without
Why aren’t antibiotics effective at treating viruses?
Viruses lack many metabolic functions
What can antibiotics only be used on?
Bacteria
What can overuse result in?
Bacterial resistance (i.e. MRSA-staph infection cannot be treated with antibiotics anymore)
What are some damages that antibiotics may cause?
Antibiotics can kill good gut bacteria or can help cause urinary tract infections
