Blood and Immune System Flashcards
What are the types of plasma proteins?
Albumins
Globulins (immunoglobulins)
Fibrinogen
What is the function of albumins?
Osmotic balance - maintain H2O levels
What is the function of globulins (immunoglobulins)?
Antibodies
Immunity
What is the function of fibrinogen?
Blood clotting
What are erythrocytes?
Red blood cells Transport O2 Packed with hemoglobin Are biconcave Have no nucleus when mature Made in bone marrow Broken down by spleen and liver
What is the function of hemoglobin in red blood cells?
Greatly increases capacity of RBC to carry oxygen
Heme: iron containing pigment
Globin: protein structure
What are leukocytes?
White blood cells or WBCs
Outnumbered by RBCs
Have a nucleus
What are the two types of white blood cells?
Granulocytes
Agranulocytes
What are granulocytes?
Small cytoplasmic granules are visible when strained
Produced in bone marrow
What are agranulocytes?
Do not have granular cytoplasm
Produced in bone marrow but are modified in lymph nodes
What are phagocytes?
Destroy invading microbes by phagocytosis
Move like an amoeba
What are the three types of Phagocytes?
Neutrophils - toxins, hemorrhage, fever, burns
Eosinophils - allergies and parasitic worms
Basophils - damage to tissues
What are lymphocytes?
The main constituents of the immune system
Yield antibodies and arrange them on their membrane
What are Platelets?
Thrombocytes
Do not contain a nucleus
Produced in bone marrow
Move through blood vessels and initiate blood clotting reactions
What are the steps in the blood clotting process?
Platelet strikes a torn blood vessel
Platelet breaks apart and releases thromboplastin
Ca and thromboplastin activates prothrombin
Becomes thrombin
Splices fibrinogen
Converted into fibrin
Wraps around cut and seals it
What is an antigen?
Molecules that cause the synthesis of antibodies when injected into another organism
What is an antibody?
Proteins found in blood that attack and neutralize substances that are foreign to the body
What is the first line of defence in the immune system?
Non-specific and external
Skin: protective
Respiratory tract: mucus and cilia sweep foreign material away from lung
Stomach: acids and protein digesting enzymes destroy microbes
Tears, saliva, mucus secretions: destroys bacterial cell walls
What is the second line of defence in the immune system?
Non-specific and internal Phagocytes destroy microbes Inflammatory response Fever Protective proteins Interferon
What is the third line of defence in the immune system?
Specific and internal
Slower, but more specific
White blood cells and lymph system are involved
WBC respond to antigens
What are some clues that the second line of defence is happening?
Pus
Inflammation
What is Interferon?
Active against viruses
Tissue cells infected by viruses produce and secrete interferon
Chemical binds to uninflected cells
These cells now produce substances that interfere with viral replication
What is cell mediated immunity?
A macrophage engulfs a bacterium, then the bacterial antigen along with the identification protein will be displayed on the macrophage membrane
The appropriate T cell and it’s receptor is presented with the antigen and is now activated
The T cell then grows and divides into Helper T cells, Killer T cells, Suppressor T cells, and Memory T cells
What is the function of a Helper T cell?
Directly stimulates a B cell by presenting an antigen to it
What is the function of a Killer T cell?
Release a chemical that forms a pore in the foreign cell membrane bearing an antigen
Cell swells and bursts
What is the function of a Suppressor T cell?
Number increases slowly
Suppress immune response
What is the function of a Memory T cell?
Recognizes original invading antigen
Can last a life time
What is antibody mediated immunity?
Antigen bonds to membrane-bound antibody on B cells
B cell divides into: many plasma cells which produce and release antibodies into blood and lymph and memory B cells that remain in bloodstream
Antibody level increases and antigens disappear from the body
Where are B-cells and T-cells produced?
Bone marrow
After the T-cells are produced, they migrate where to get modified?
The thymus gland
