Innate and Adaptive Immunity

Question 1

Organs involved in the immune system

Answer 1

Thymus
Tonsils + adenoids
Lymph nodes
Spleen
Peyer’s patches + appendix
Bone marrow

Question 2

Immunity defined

Answer 2

the body’s capacity to resist and combat infections

Question 3

Innate Immunity

Answer 3

comprises of anatomical, mechanical and physiological barriers as well as cellular and inflammatory mechanisms which are immediately activated in the presence of an antigen, 1st line defence, 2nd line defence

Question 4

Adaptive Immunity

Answer 4

specialized type of immunity which is developed after having an infection or receiving vaccination

Question 5

Characteristic of innate immunity

Answer 5

Immediate (within minutes)
Nonspecific
Lower potency
No memory

Question 6

Characteristic of adaptive immunity

Answer 6

Takes a few days (3-7 days)
Specific
High potency
Memory cells

Question 7

The features of adaptive immunity

Answer 7

Recognition of self vs non-self: Major Histocompatibility complex (MHC) is protein markers on the body cell surface which are recognized by T cells.
Specificity: B and T cells make receptors for only one type of antigen
Diversity: Collectively B and T cells have receptors for over 2 billion antigens.
Memory: B and T cells make memory cells which allows prompt response on re-exposure to infection

Question 8

Antibodies

Answer 8

made by plasma cells which are B cells activated by T-helper cells

Question 9

Innate Immunity Cells and their function

Answer 9

Neutrophils: are a type of phagocytes that engulf microbes and debris
Eosinophils: these cells target parasites such as worms which are too large to be engulfed
Basophils: the cells contain granules which induce inflammation.
Mast cells: granule rich cells found in skin and mucosa and are one of the first defence cells of the innate immune system.
Macrophages: monocytes give rise to macrophages; these cells are large phagocytes.
Dendritic cells: these cells alert
the adaptive immune system of the presence of microbes.
Natural Killer cells: cells of the innate system that contains viral infections, usually alerted by interferons and cytokines.

Question 10

Adaptive Immunity Cells and their function

Answer 10

B lymphocytes
These cells recognize specific antigens
These are antigen presenting cells that activates T cells
Differentiate into plasma cells which produce antibodies which play a primary role in humoral immunity
T lymphocytes
These cells recognize specific antigens
There are different types of T cells such as T-helper cells, cytotoxic T cells, T-regulatory cells.
Memory cells
T memory cells: rapidly converted into effector T cells upon re-exposure to the specific invading antigen, thus providing a rapid response to past infection.
B memory cells: these cells remember the pathogen for faster antibody production

Question 11

Complement cascade

Answer 11

part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and attack the pathogen’s cell membrane

Question 12

Plasma cells

Answer 12

type of white blood cell that develop from B cells that have been activated