Lympathic Practical Study

Lymphatic system

Returns interstitial fluid to bloodstream and provides immune defense

Lymph

Fluid derived from interstitial fluid that enters lymphatic vessels

Interstitial fluid

Fluid between cells formed from blood plasma

Lymphatic capillaries

Smallest vessels that collect lymph; closed at one end

Lymphatic vessels

One-way vessels with valves that carry lymph

Lymph trunks

Larger vessels that drain lymph from regions of the body

Lymph ducts

Largest vessels that empty into subclavian veins

Thoracic duct

Drains lymph from most of the body into left subclavian vein

Right lymphatic duct

Drains lymph from right upper body into right subclavian vein

Cisterna chyli

Enlarged sac that collects lymph from lower body before thoracic duct

Primary lymphoid organs

Sites where lymphocytes mature

Bone marrow

Site of B cell maturation and origin of all lymphocytes

Thymus

Site where T cells mature; located superior to heart

Secondary lymphoid organs

Sites where lymphocytes encounter antigens

Lymph nodes

Filter lymph and house immune cells

Spleen

Filters blood and removes old red blood cells

Tonsils

Lymphatic tissue that traps pathogens entering mouth and nose

Peyer’s patches

Lymphoid nodules in ileum that monitor intestinal bacteria

Appendix

Contains lymphoid tissue for immune function

Cortex of lymph node

Outer region containing B cells and follicles

Medulla of lymph node

Inner region containing T cells and macrophages

Trabeculae

Connective tissue extensions in lymph nodes

Lymphatic nodule

Cluster of lymphocytes within lymphoid tissue

Innate immunity

Non-specific defense present at birth

Physical barriers

Skin and mucous membranes that block pathogens

Chemical barriers

Substances like stomach acid and lysozyme that destroy pathogens

Mast cells

Release histamine to promote inflammation

Neutrophils

Phagocytic cells that respond quickly to infection

Macrophages

Large phagocytic cells that engulf pathogens

Natural killer cells

Destroy infected or abnormal cells

Adaptive immunity

Specific immune response developed over time

Cell-mediated immunity

Response involving T cells

Humoral immunity

Response involving B cells and antibodies

T cells

Destroy infected cells directly

B cells

Differentiate into plasma cells to produce antibodies

Antibodies

Proteins that bind to specific antigens

Immunological memory

Faster response upon second exposure to antigen

Primary response

Initial slow response to antigen

Secondary response

Faster and stronger response upon re-exposure

Cervical lymph nodes

Located in neck

Axillary lymph nodes

Located in armpit

Inguinal lymph nodes

Located in groin

Thoracic lymph nodes

Located in chest

Pelvic lymph nodes

Located in pelvic region

Lumbar lymph nodes

Located in lower back

Mesenteric lymph nodes

Located in mesentery

Abdominal lymph nodes

Located in abdomen

MALT

Mucosa-associated lymphoid tissue protecting mucous membranes

Adenoids

Pharyngeal tonsils located in nasopharynx

Palatine tonsils

Located on sides of oropharynx

Lingual tonsils

Located at base of tongue

Tubal tonsils

Located near opening of auditory tubes