Blood groups and introduction to blood Flashcards
(80 cards)
1
Q
What is the function or red blood cells and what is another name for it?
A
The function of the red blood cell is to transport oxygen as oxyhaemoglobin as it contains haemoglobin. Another name for it is a Erythrocyte.
2
Q
What is the function of a platelet
A
Blood clotting
3
Q
What is the function of a lymphocyte
A
B Cells produce antibodies.
Also T-killer cells and T-helper cells
4
Q
What is the function of a neutrophil
A
It is an example of a phagocyte, carries out phagocytosis. Takes in bacteria and destroys it.
5
Q
How to blood groups classify blood?
A
Using marker proteins that acts as antigens on the Red Blood cell.
6
Q
What do the antigens do on the red blood cell
A
affects the ability of the Red blood cells to provoke an immune response.
7
Q
If the blood of the donor and the receiver have different blood groups, what will happen to the blood?
A
The blood will clump together also known as agglutinate, in which they will then break apart and block capillaries
8
Q
What antigen and antibodies does blood type A have?
A
Antigen A and anti-B antibodies.
9
Q
What antigen and antibodies does blood type B have?
A
Antigen B and anti-A antibodies
10
Q
What antigen and antibodies does blood type AB have
A
Antigens A and B but no antibodies
11
Q
What antigen and antibodies does blood type O have?
A
No antigens but anti-A and anti-B antibodies
12
Q
Blood Type AB is a universal _______
A
Receiver
13
Q
Blood Type O is a universal ________
A
Donor
14
Q
Blood Type A can donate blood to…
but can receive from….
A
donate - A and AB
receive - A and O
15
Q
Blood Type B can donate blood to…
but can receive from….
A
donate - B and AB
receive - B and O
16
Q
Blood type AB can donate blood to…
but can receive from….
A
Donate - AB
Receive - A, B, AB, and O (universal receiver)
17
Q
Blood Type O can donate blood to…
but can receive from….
A
donate - A, B, AB and O (universal donor)
Receive - Only O
18
Q
What is haemolytic disease?
A
A severe immune reaction caused by mothers newly acquired antibodies which attack the unborn baby’s blood cells.
19
Q
What does haemolytic disease cause the baby to be?
A
extremely anaemic
20
Q
When do the Rh Antigens pass from the baby into the mother?
A
During child birth
21
Q
How is Haemolytic disease treated?
A
Mother takes an injection that destroys the Rhesus antigens causing the second baby to be safe.
22
Q
Define anaemia
A
Where the blood has little red blood cells and/or has is low in haemoglobin.
23
Q
What are the symptoms of anaemia?
A
Tiredness, faint/weak, shortage of breath and headache
24
Q
How can anaemia be treated?
A
Diet with high amount of iron. Or in severe cases a blood transfusion.
25
What is the first line of defence?
The first line of defence is the skin
- the skin provides formidable physical barriers to the entry of pathogens
- Healthy skin is rarely penetrated by microorganisms
- Skin produces chemical secretions that inhibit the growth of bacteria and fungi.
- Tears, mucus, saliva help wash away microbes (bacteria), these also contains enzymes (e.g lysozyme) that digests bacteria.
26
What is the second line of defence?
The second line of defence is a range of non-specific defences inside the body that inhibits and/or destroys pathogens. They react to the presence of any pathogen regardless of which species it is. WBC (leukocytes) are involved-
- Eosinophils
- Basophils
- Neutrophils and macrophages
27
In the second line of defence what do eosinophils, basophils and neutrophils and macrophages do?
Eosinophils - the produce toxic proteins against certain parasites also does some phagocytosis. (for antimicrobial substances)
Basophils - Releases an anticoagulant (heparin) and histamine promoting inflammation (for inflammation and fever)
Neutrophils and macrophages - engulfs and destroys foreign material (e.g bacteria) they are phagocytic white blood cells
28
Where are phagocytes formed?
Produced in the bone marrow by stem cells.
29
What are neutrophils?
60% White blood cell. They squeeze out of capillaries. Large number of them are released during infections. Dies after digesting bacteria and large amounts of dead neutrophils make puss.
30
What are macrophages?
They are larger than neutrophils and found in organs and not the blood. The are made in bone marrow as MONOCYTES and then once they reach organs they become macrophages. They initiate immune responses as they display antigens from pathogens to the lymphocytes.
31
What is the 3rd line of defence?
The 3rd line of defence is once the pathogen is identified by the immune system. A specific response is made from the WBC called the lymphocytes. These lymphocytes coordinate a range of specific responses to the pathogen.
32
What does resistance of pathogens depend on
General health and diet. E.g deficiency of vitamin C leads to weakness of connective tissue causing more open wounds and easy infections (e.g scurvy)
33
What are the primary (natural) line of defence
They are mechanisms that prevent the pathogen entering the body
- eyes (tear ducts) produces antibodies and lysozyme
- Ears produces wax that traps pathogens
- mucous membranes, found in the gut, genital area, anus, ears, nose, and respiratory passages. globlet cells produces mucus which lines the passages and traps pathogens. in respiratory tract, ciliated cells waft mucus in which is swallowed to the stomach causing the pathogens to be destroyed.
- Skin is the physical barrier to pathogens
34
What are the actions of phagocytes?
1 - detection - phagocytes detects microbes by chemicals they give off and sticks microbes to its surface
2 - ingestion - microbe is engulfed by the phagocyte wrapping pseudopodia around it to form a vesicle
3 - phagosome forms - a phagosome (phagocytic vesicle) is formed, which encloses microbes in a membrane
4 - fusion with lysosome - phagosome fuses with lysosome which contains enzymes that can digest microbe.
5 - Digestion - microbes are broken down by enzymes
6 - Discharge - indigestible material is digested from the phagocyte cell (exocytosis)
35
what are the interaction of microbes and phagocytes?
- microbes kill phagocytes by producing toxins
- microbes evade immune system by entering phagocytes which they prevent fusion of the lysosome with phagosome and multiply inside the phagocyte
- dormant microbes hide inside phagocytes.
36
What examples can damage body tissues?
Physical agents, microbial infection and chemical agents.
37
What defensive response is triggered when there is damage to body tissue and what are its symptoms?
Inflammation.
| Symptoms are pain, redness, heat and swelling.
38
What are the functions of inflammation?
1 - destroys the cause of infection and remove it and its products from body
2 - (if fails) limit the effects on the body by confining the infection to a small area
3 -replacing or repairing tissue damaged by infection.
39
What is the first stage of inflammation?
The blood vessels increase in diameter and permeability (vasodilation). which increases blood flow to the area and allow defensive substances to leak into tissue spaces.
40
What is the second stage of inflammation?
Phagocyte migration and phagocytosis - within one hour of the injury, phagocytes appear on the scene. they squeeze between cells of blood vessel walls to reach the damaged area where they destroy invading microbes.
41
What is the third stage of inflammation?
Tissue repair - function cells/supporting connective cells create new tissue to replace dead/damaged cells
42
What do histamines and prostaglandins do?
They are released by damaged cells, attracts more and more phagocytes to the infection
43
What is an abscess
A collection of dead phagocytes, damaged tissue and various body fluids also known as pus.
44
What are the 2 types of cells of the immune response?
B cells and T cells (both lymphocytes)
45
where do B-cell lymphocytes mature, concentrate and what do they produce?
They mature in bone marrow, concentrate in the lymph nodes and spleen and produce antibodies
46
What type of response is B-Cell lymphocytes
Humoral response.
47
Where do T-cell lymphocytes mature
Thymus
48
What type of response is T-cell lymphocytes
Cell mediated response.
49
Where do B and tell Lymphoctye cells circulate and why
They circulate in the blood and lymph and circulation ensures that they come into contact with pathogens and each other.
50
how many different types of B lymphocytes are there and what makes it different?
There are about 10 million different b-lymphocytes and the all make different antibodies. The huge variety is caused by genes coding for antibodies changing slightly during development.
51
True or false, there are small groups of clones of each B-lymphocyte
True
52
Where are the antibodies embedded and what are they called?
They are embedded on the plasma membrane of the cell and are called antibody receptors.
53
How are the antigens present to b cells
By macrophages.
54
What happens when receptors on the membrane recognise the antigen on the macrophage?
B-lymphocytes divide rapidly by mitosis. this is called clonal selection. This causes the B-lymphocytes to be activated.
55
What happens to the activated B-lymphocytes?
They divide again and form plasma cells that produce antibodies which travel to blood and lymph (this is the primary immune response)
56
What happens to the spare activated B-lymphocytes?
They become memory cells and can last a lifetime, they do not secrete any antibodies but they provide the body's immunological memory
57
What do the memory cells do?
They divide rapidly as soon as the antigen is reintroduced. They can easily destroy pathogen/infection before any symptoms shows this is the secondary immune response.
58
What are antibodies?
They are also known as immunoglobulins (proteins). They all contain 4 polypeptide chains (2 long chained (heavy) and 2 short chained (light)). The chains are held by disulfide bridges. Each antibody has 2 identical antigen binding sites - variable regions. The order of amino acids in the variable region determines the shape of the binding site. which are only specific to one antigen.
59
What are antigens?
Substances that are recognised as foreign by the immune system that stimulate production of antibodies and an immune response. they are often proteins found on the surface of a bacteria/virus. Can also be on the cell surface of foreign tissue such as organ transplants or a blood transfusion. can also be free molecules from toxins released by microbes.
60
What is neutralization
where antigens are toxins which are rendered harmless if they are blocked b being bound to an antibody.
61
Simples steps to humoral immunity
1 - B cell has a antibody receptor specific to the shape of antigen
2- selected b cell divides by mitosis and forms plasma and memory cells.
3- Plasma cells secrete antibodies that combine with antigen
4 - SOME TIME LATER - same antigen enters again and memory cells rapidly divide via mitosis forming many more plasma cells (this is far more rapid than the first exposure to this antigen)
62
What do mature t cell receptors have
Similar structure to antibodies and are specific to one antigen.
63
How are t cells activated
they are activated when the receptor comes into contact with antigen on surface of another host cell (e.g macrophage or invaded body cell)
64
What happens after the t cells are activated?
The cell will divide by mitosis and form
- t helper cells that secrete cytokines to help b cells divide and stimulate macrophages.
- Killer t cells that kills body cells displaying antigen
- suppressor t cells that stop immune responses once the pathogen is destroyed
- memory t cells that remain in body as immunological memory.
65
What does AIDS stand for
Acquired immune deficiency syndrome.
66
What is the pathogen that causes aids identified as?
A retrovirus that contains RNA that selectively infects helper t cells.
67
What is the retrovirus that selectively infects helper t cells called and what does it cause?
Human immunodeficiency virus (HIV) and it causes the collapse of the immune system
68
Structure of a HIV virus
- Capsid - protein coat that protects RNA
- Viral envelope - piece of plasma membrane
- Antigens - attach to t cells and macrophages
- reverse transcriptase - 2 copies of this important enzyme transcribe the RNA into DNA once in host cell
- Nucleic acid - Two identical strands of RNA that contain genetic blueprint for making more HIV viruses.
69
How does HIV infect a t cell
1- HIV attracted to receptors on helper t cell
2- HIV fuses with plasma membrane on t cell and capsid is removed by enzymes
3- reverse transcriptase cause formation of viral DNA (using RNA as a template)
4- complementary strand of DNA formed
5- Double-stranded DNA incorporated into host cells chromosomes
6 - viral genes transcribed into MRNA molecules
7- viral mRNA translated into HIV proteins
8 - Assembly of capsids around viral genomes
9 - budding of new virus from the host cell.
70
How do antibodies work
Opsonin - attachment site binds receptor on phagocyte and variable site to antigens allowing engulfment
lysis - antibodies attract enzymes which digest cell wall of bacterium resulting in lysis (bursting)
Neutralisation - antibodies bind toxins produced by bacteria, neutralising them
precipitation - antibodies can cause soluble antigens to precipitate out increasing engulfment by pathogens
Agglutination - bacteria clump together making them less likely to spread and increase engulfment.
71
Why is second response better than primary response?
Primary response is slow, results in low antibody production and does not confer with immunity.
Secondary response is rapid, results in high antibody production and produces long-lasting immunity.
72
What are the 3 stages of HIV infection
1- HIV positive with little/no symptoms
2- some symptoms, low helper t Cell count
3 - clinical AIDS symptoms appear.
73
How does HIV Transmit?
- In blood, vaginal secretion, semen, breast milk and across the placenta
- blood transfusion in less developed countries
- Homosexual activity and intravenous drug use, heterosexual transmission.
74
Symptoms of AIDS
Fever, skin inflammation, diarrhea, Kaposi's sarcoma, oral thrush, eye infections etc.
75
Why is it so difficult to develop a vaccin against HIV?
Antigens change and there is an antigenic mutation.
76
What is a vaccine?
A preparation containing antigenic material e.g. MMR
77
What is natural active immunity?
Acquired due to infection
first contact - getting disease
second contact - immunity achieved.
78
What is natural passive immunity?
No activation for B and T Cells. Antibodies acquired through mother (temporary-short term)
79
What is artificial active immunity?
Vaccine which contains antigens and causes primary response.
80
what is artificial passive immunity?
Human antibodies injected (short term)
