The Lymphatic System

Published on 6th June 2018


Drains tissue spaces of escaped protein and fluid and returns to cardio-vascular system 

  • Transports fats from intestines to blood 
  • Produces Lymphocytes to protect body from foreign bodies, and disease 
  • Acts as a filter to prevent spread of pathogens from blood stream 

Two types of Lymphocytes:

  • T-Cells – destroy foreign cells/viruses/cancer cells  
  • B-Cells – secrete anti-bodies against foreign substances 



  • Lymph (fluid derived from plasma) 
  • Lymph Vessels/Capillaries
    • Have valves. Run alongside arteries and veins
    • Very thin permeable walls that large particles including bacteria can permeate
    • Some contain involuntary muscles 
    • Found throughout body except C-N-S, cartilage, teeth
  • Lymph Nodes 
    • Bean shaped 1-25mm in length
    • Produce lymphocytes in outer cortex 
    • Filter lymph  
    • Found around major arteries 

Lymphatic Tissue

  • Found in mucous membranes of gastro-intestinal tract, respiratory passageways, urinary tract, reproductive tract, and organs of body 


  • Collection of lymphatic tissue in a mucous membrane
  • Protect against invasion of foreign substances 

Spleen 12cm

  • Largest mass of lymphatic tissue 
  • Stores and releases blood in emergency 
  • Produces activated lymphocytes 
  • Ingests bacteria and worn out erythrocytes and thrombocytes 

Peyer’s Patches 

  •  A collection of lymphatic tissue found in the small intestines, mainly in the ileum 

Thymus Gland between lungs

  • Conspicuous in Infant  
  • Atrophied but still functional in adult 
  • Activates T Cells and distributes to other lymphoid tissue around the body

Thoracic duct and right lymphatic duct

  • Collects lymph from all lymph vessels 
  • Drains into left and right jugular veins



1.  What is the lymphatic system?

a. A network of tubes throughout the body that drains fluid from tissues and returns it to the bloodstream
b. A transport system for carrying nutrients around the body
c. A series of glands that secrete chemicals called hormones into the blood 
2.  What are the main functions of the lymphatic system?
a. Managing fluid levels in the body, making hormones that regulate metabolism, and filtering out bacteria
b. Managing fluid levels, maintaining the sense of balance, and housing types of white blood cells
c. Managing fluid levels, filtering out bacteria, and housing types of white blood cells 
3.  What are lymph nodes?
a. Glands made of lymph tissue that are found at various sites around the body
b. Abnormal scar tissue that prevents the free flow of lymph through the vessels
c. Special clusters of nerve cells that allow the lymphatic system to communicate directly with the brain. 
4.  Which organs belong to the lymphatic system?
a. The spleen and thymus
b. The pancreas and the liver
c. The kidneys and bladder 
5.  What happens to the excess fluid that the lymphatic system removes from the tissues?
a. Fluid that the body needs is returned to the bloodstream but excess fluid is piped directly to the bladder for excretion
b. Fluid that the body needs is returned to the bloodstream but excess fluid is directed to the mouth to aid in saliva production
c. All collected fluid is returned to the bloodstream 
6. What is oedema?
a. A type of cancer that affects the lymphatic system
b. Temporary swelling of certain parts of the body
c. The collective name for the largest lymph vessels 


Anatomy and Physiology On-Line
Gill Tree Training


View all messages

Anatomy and physiology online courses - Free e-book
Free e-book

10 Top Study Tips to Help You Pass Your Anatomy and Physiology Exam

Anatomy and physiology online courses - free trial
Free Trial

No Commitment.
No hidden fees.
No credit card required.

Start Today


"The level 3 Anatomy and Physiology course has been really worthwhile, and provided me with a much needed foundation in A&P to go onto Osteopathy. Thanks for providing such an accessible, and easy to follow study program."

- gill Tree -

Newsletter Signup

Anatomy & physiology courses online - refund policy


ITEC Level 3 certificate in Anatomy, Physiology and Pathology
British Register of Complementary Practitioners
Association Systematic Kinesiology
BowenTraining UK

Get in Touch

GM Tree Training Ltd
5 Clumber Drive
Somerset BA11 2LG
United Kingdom
T: +44 (0)7392 745790

Contact us

Secure transactions

Powered by WordPay

Mastercard Visa American Express Maestro JCB

This website uses cookies in order to help provide the best experience for our users. Find out more.

OK, I'm good with that