I & L Flashcards
What is the function of memory cells?
They remember the same pathogen for faster antibody production in future infections.
What is the function of suppressor T-cells?
They modulate the immune system, maintain tolerance to antigens and prevent autoimmune disease.
Plasma cells make?
Antibody molecules.
They bind to the target antigen and initiate its destruction of neutralization.
The lymphatic system consists of what?
Two semi-independent parts:
- lymphatic vessels
- lymphatic tissues and organs
What are the lymphatic system functions?
- Transport fluids back to the blood.
- Body defense and resistance to disease.
What is lymph?
Excess tissue fluid carried by lymphatic vessels.
Properties of lymphatic vessels are:
- one way system
- no pump
- lymph moves toward the heart
- milking action of skeletal muscle
- rhythmic contraction of smooth muscle in vessel walls
What does the spleen do?
- filters blood
- destroys worn out blood cells
- forms blood cells in the fetus
- acts as a blood reservoir
Where is the spleen located?
Left side of the abdomen
What does the thymus do?
- functions at peak levels during childhood.
- produces hormones such as thymosin which programs lymphocytes.
Where is the thymus located?
In the throat overlying the heart
What do the tonsils do?
-Trap and remove bacteria
Where are the tonsils located?
Small masses of lymphoid tissue around the pharynx
What causes tonsillitis?
Congestion of bacteria
What does the Peyer’s Patches do?
Capture and destroy bacteria in the intestine.
Where do Peyer’s Patches look like and where are they located?
Resemble tonsils in structure and found in the wall of the small intestine.
What harmful materials enter the lymph vessels?
Bacteria
Viruses
Cancer cells
Cell debris
What do lymph nodes do?
Filter lymph before it is returned to the blood.
Two defense cells within the lymph nodes are?
Macrophages
Lymphocytes
What are macrophages?
Engulf and destroy foreign substances.
What are lymphocytes?
Provide immune response to antigens.
What does lymphatic vessels do?
- Collects lymph from lymph capillaries.
- Carries lymph to and away from lymph nodes.
- Returns fluid to circulatory veins near the heart.
What are the two defense systems for foreign materials?
-nonspecific defense and specific system
What does the nonspecific defense system do?
- protects against a variety of invaders
- responds immediately to protect the body from foreign materials.
What does the specific defense system do?
Is required for each type of invader.
What are the first line of defense?
- Skin
- Stomach mucosa
- Saliva and lacrimal fluid contain lysozyme
What does the skin do for defense?
- physical barrier to foreign materials
- pH of the skin is acidic to inhibit bacterial growth
- sebum is toxic to bacteria
- vaginal secretions are very acidic
What is sebum?
Oily and waxy substance that waterproofs and lubricates the skin and hair.
What does stomach mucosa do for defense?
- secretes hydrochloric acid
- has protein-digesting enzyme
What does saliva and lacrimal fluid do for defense?
-mucus traps microorganism in digestive and respiratory pathways.
What are the second line of defense?
Defense cells
- phagocytes
- natural killer cells
What does phagocytes dos for defense?
Are neutrophils and macrophages
- engulfs foreign materials into a vacuole
- enzymes from lysosomes digest the material
What does the natural killer cells do for defense?
Can destroy virus-infected cells.
What is the inflammatory response?
- triggered when the body tissues are injured.
- produces four Cardinal signs
- results in a chain of events leading to protection and healing.
What are the four Cardinal signs?
- redness
- heat
- swelling
- pain
What are the functions of an inflammatory response?
- prevents the spread of damaging agents
- disposes of cell debris and pathogens
- sets the stage for repair
What are complement proteins?
- a group of at least 20 plasma proteins
- activated when they encounter and attach to cells
- damages foreign cell surfaces
- has vasodilators, chemotaxis and opsonization.
What is interferon?
- secreted proteins of virus-infected cells
- bind to healthy cell surfaces to inhibit viruses binding.
What is a fever?
- abnormally high body temp
- hypothalamus heat regulation can be reset by pyrogens (WBC)
- high temp inhibit the release of iron and zinc from liver and spleen needed by bacteria.
- fever increases the speed of tissue repair.
What is the hypothalamus?
Region of the brain that coordinates both autonomic nervous system and the activity of the pituitary
What’s the third line of defense?
Specific defense: the immune system
What does the third line of defense do?
Antigen specific - recognizes and acts against particular foreign substances
Systemic - not restricted to the initial infection site
Has memory - recognizes and mounts a stronger attack on previously encountered pathogens.
What are antigens?
Any substance capable of exciting the immune system and provoking an immune response
What are some examples of common antigens?
- foreign proteins
- nucleic acids
- large carbohydrates
- some lipids
- pollen grains
- microorganisms
What are self-antigens?
- our cells in another persons body can trigger an immune response because its foreign.
- our immune cells don’t attack our own proteins
- human cells have many surface proteins
What are the cells of the immune system?
- Lymphocytes
- macrophages
What is an lymphocytes?
Originates from hemocytoblasts in the red bone marrow.
- B lymphocytes= become immunocompetent in the bone marrow.
- T lymphocytes= become immunocompetent in the thymus
What is a macrophage?
Become widely distributed in lymphoid organs.
What kinds of T cells are there?
- Cytotoxic T cells (killer T cells)
- Helper T cells
- Suppressor T cells
What does the Cytotoix T cells (killer T cells) do?
- specialized in killing infected cells
- insert a toxic chemical (perforin)
What does the helper T cells do?
- recruit other cells to fight the invaders
- interact directly with B cells
What does the suppressor T cells do?
- release chemicals to suppress the activity of T and B cells
- stop the immune system response to prevent uncontrolled activity
- a few members of each clone are memory cells.
What is active immunity?
- B cells encounter antigens and produce antibodies
- can be neutral or artificially acquired
What is passive immunity?
- antibodies are obtained from someone else
- naturally from a mother to her fetus
- artificially from immune serum or gamma globulin
- immunological memory doesn’t occur
- protection provided by borrowed antibodies
What types of grafts are there?
- autografts
- isografts
- allografts
- xenografts
What grafts are ideal donors?
Autografts and isografts
Which graft is never successful?
Xenografts
Which grafts can be more successful with a closer tissue match?
Allografts
What is a autograft?
Tissue transplanted from one sit to another on the same person.
What is a isografts?
Tissue grafts from an identical person (twin).
What is an allografts?
Tissue taken from an unrelated person.
What is a xenografts?
Tissue taken from a different animal person.
What is an autoimmune disease?
- The immune system doesn’t distinguish between self and non self.
- the body produces antibodies and sensitized T lymphocytes that attack its own tissues.
What are some examples of autoimmune diseases?
- multiple sclerosis
- juvenile diabetes
- rheumatoid arthritis
What is multiple sclerosis?
- White matter of brain and spinal cord are destroyed.
- symptoms= vision loss, pain, fatigue, impaired coordination.
- PT and meds
What is juvenile diabetes?
- Destroys pancreatic beta cells that produce insulin.
- increased thirst, frequent urination, hunger and fatigue.
- insulin therapy, diet and exercise.
What is rheumatoid arthritis?
- Destroys joints.
- painful swelling, bone erosion and joint deformity.
- meds
What is a lymph capillary?
- fluid leaks into Lymph capillaries
- capillaries are anchored to connective tissue by filaments
- higher pressure on the inside closes mini-valves
What is AIDS?
- the body’s inability to fight infections.
- flu-like symptoms, fever, sore throat, night sweats
- drugs can slow progress but no cure.
What is lymphedema?
- swelling arms or legs
- pain and swelling
- wrapping, massages, exercise
What is Hodgkin’s disease?
- cancer of the the lymphatic system
- swelling of lymph nodes
- chemo, radiation
What is splenomegaly?
- enlarged spleen
- sometimes no symptoms, feeling full
- caused by viral or bacterial infections
- meds
Four different types of pathogens?
Bacteria
Virus
Fungi
Protists
What did Dr. Fleming discover?
Penicillin
Function of lymphatic vessels?
Carry lymph
What is the function of the first line of defense?
Designed to keep the bad guys out.
What is the function of the second line of defense?
Slow down the bad guys.
Who is Edward Jenner?
Smallpox vaccine.
Who is Jonas Salk.
Polio vaccine
What is the difference cow pox and small pox?
Smallpox highly infectious disease.
Cowpox infection that gives gives immunity to smallpox. Develops antibodies
Last death due to smallpox?
1977
Where are the last two cases of smallpox located?
USA and Russia
Function of mucus?
Protect epithelial cells against bacteria.
Function of cilia?
Move particles up to throat where they are either coughed or sneezed out.
Function of nasal hairs?
A first line of defense against pathogens.
What are pyrogens?
Produced by a bacterium that produces fever.
Define immunity?
Ability to resist a particular infection or toxin.
Example of artificially acquired active immunity?
Vaccine
Example of naturally acquired passive immunity?
Antibodies pass from mom to fetus, or infant
Example of naturally acquired active immunity?
Infection contact with pathogen.
Example of artificially passive?
Injection of immune serum.
Four diseases you have been immunized against?
Chickenpox
Mumps
Rotavirus
Wooping cough
B cells reside where?
Bone marrow and migrate to the spleen and lymph tissue
Helper T cells secrete what?
Antibodies
Macrophages
Lymphatic vessels move lymph towards?
Towards the neck.
