The Lymphatic System

Question 1

What are the main functions of the lymphatic system?

Answer 1

• Maintain fluid balance
• Eliminate foreign matter
• Provide immune cells for defense

Question 2

What are the four main components of the lymphatic system?

Answer 2

• Lymph
  
  • Fluid
  • Collected from interstitial spaces of tissues
  • Returned to bloodstream
• Lymphatic Vessels
  
  • Transports lymph
• Lymphatic Tissue
  
  • Lymphocytes and macrophages
• Lymphatic Organs
  
  • Lymph cells

Question 3

Describe the route of lymph fluid back to the bloodstream

Answer 3

1. Lymphatic capillaries
2. Collecting vessels
3. Lymphatic trunks
4. Collecting ducts
5. Filtered through lymph nodes
6. Subclavian veins

Question 4

Describe the two lymph collecting ducts

Answer 4

• Lymph drainage
• Thoracic duct
  
  • Entire body except
  • RHS of head and neck
  • RHS of thorax
  • Right upper extremity
• Right lymphatic duct
  
  • Most of the body
• There is NO left lymphatic duct!

Question 5

What are the seven types of lymphatic cells?

Answer 5

• Neutrophils
• Natural killer cells
• T lymphocytes
  
  • Tc: Cytotoxic T cells
  • TH: T helper cells
  • TR: Regulatory T cells
  • Memory T cells
• B lymphocytes
  
  • Antigen presenting cells
  • Some become memory cells
• Macrophages
  
  • Antigen presenting cells
  • Phagocytic cells
  • Ingest and destroy foreign matter
• Dendritic cells
  
  • Engulf foreign matter
• Reticular cells
  
  • Antigen presenting cells
  • Stroma of lymphatic organs

Question 6

What are the four lymphoid organs?

Answer 6

• Thymus
  
  • Behind sternum
  • Extends upwards into root of neck
  • Influences T cells maturity
• Lymph node
  
  • Cleanses lymph
  • Site of B and T cell activation to fight infection
• Spleen
  
  • Blood filter
• Tonsils
  
  • Lymphatic tissues
  • At entrance to pharynx
  • Guard against ingested or inhaled pathogens