The Immune System Flashcards
1
Q
Innate Immunity
A
- Features phagocytes and dendrites
- always active against infection
- doesn’t have specific targets (nonspecific immunity)
- Features phagocytes (i.e dendrites, macrophages, neutrophils)
2
Q
Adaptive immunity
A
- Features B-cells and T cells
- Targets specific pathogens
- initially is slower to act
- Subsequent actions are faster due to immunological memory ability.
- Features B-cells and T-cells
3
Q
Bone marrow
A
- produces the leukocytes
- Site of B-cell maturation
4
Q
Spleen
A
- location of blood storage,
- Site of activation of B-cells into plasma cells
5
Q
Thymus
A
- Site of T-cell maturation
- They are the agent of “cell-mediated” immunity
- Located infront of pericardium
6
Q
Lymph nodes
A
- A place for immune cells to communicate
- Site of activation of B-cells
7
Q
Leukocytes
A
- Granulocytes : Contain toxic granules that fight pathogens
- Neutrophils , eosinophils, basophils - Agranulocytes: Lymphocytes, monocytes / Macrophages
- Precursor is hematopoietic stem cell
8
Q
THE INNATE IMMUNE SYSTEM
A
- Noncellular Nonspecific defenses
9
Q
Components of innate immunity
A
Skin Mucous membranes Gastrointestinal tract Complement system Interferons Macrophages Antigen-Presenting cells Natural killer cells Granulocytes
10
Q
Skin
A
- First line of defense
- Contains “defensins” which are antibacterial enzymes
11
Q
Mucous membranes
A
- Cilia traps particulates, transport it out.
- Prevents virus entry into lung tissue
- Those in the eye and mouth produce lysozyme
12
Q
Gastrointestinal tract
A
- Stomach acid
- Presence of good bacterial colonies; tough competition against invaders for resources
13
Q
Complement system
A
- Blood proteins
- Initially inactive → encounters pathogen → activated through classical (w/ Ab) or Alternative pathway (w/o Ab)
- Form membrane attach complexes; putting holes in bacterial membrane.
14
Q
Interferons
A
- Protects against viral replication and dispersion
- Produced by infected cells
- Increases MHC antigen presentation
- Induces flu-like symptoms
- Decreases cell membrane permeability.
15
Q
Macrophages
A
- Agranulocytes derived from monocyte
- Some are resident in tissues
- Phagocytize bacteria, virus, fungus, and parasites.
- Phagocytize then presents fragment on MHC-II
- MHC-II also presents exogenous proteins (antigen)
- All nucleated cells present MHC-I
- MHC-I displays endogenous proteins (antigen)
- Releases cytokine that induces Inflammation
- Have receptors known as Pattern Recognition Receptors (PRR)
- i.e Toll like Receptors (TLR)
- Recognize specific pathogens
