Lymphatic System and Immunity

Question 1

Describe the functions of the lymphatic system

Answer 1

· Maintains fluid balance in the internal environment
- Interstitial fluid is absorbed by tissue cells or reabsorbed by
the blood
- Oedema (fluid retention) may lead to tissue destruction
· Lymph vessels act as “drains” to collect excess tissue fluid
and return it to the venous blood
· Returns certain substances to the general circulation

Question 2

Describe lymphatic vessels and transport of lymph

Answer 2

· Lymph
· Lymphatic vessels
· Lymph nodes
- Mechanical filtration
- Biological filtration
- Haematopoiesis
· Tonsils -
- Pharyngeal tonsils - posterior opening of nasal cavity
- Palatine tonsil - each side of throat
- Lingual tonsil - base of tongue
· Thymus - in Mediastinum
- Where T cells are developed
· Spleen - Upper left quadrant
-
· Bone marrow - Creates RBC + WBC

Question 3

Describe the components of innate immunity

Answer 3

· Epithelial barrier cells
· Phagocytic cells
- Neutrophils and macrophages
· Natural killer (NK) cells
· Cytokines
Trigger or regulate immune responses

Question 4

Describe the three lines of defence against pathogens

Answer 4

Innate Immunity
· First
- Skin
- Mucous membranes
- Secretions of skin and mucous membranes
· Second
- Phagocytic Leukocytes
- Antimicrobial proteins
- Inflammatory response
- fever
Adaptive Immunity
· Third
- Lymphocytes
- Antibodies
- Memory cells

Question 5

Describe the responses of B and T cells

Answer 5

B Cells - Produce antibodies that attack pathogens
T cells - Look at cellular structure of the pathogen

Question 6

Describe the five classes of antibodies

Answer 6

Go And Meet Doctor Ed

IgG = 80% only antibody to cross placenta, predominant in second immune response
IgA = 15% - found in nose
IgM = 5% - mediates - found in lymph fluid & blood
IgD = 1% -
IgE = <1% - found in patients with allergies