Level 3 - Exploring the Lymphatic System

• Mathematics
• Further Education (Key Stage 5)

Exploring the Lymphatic System: Unveiling the Hidden Network

Learning Objective

Understand the composition and location of the components of the lymphatic system.

What do you already know about the lymphatic system?

00:51

What does ciculatory system transports in our body?

01:25

The blood system does not consist of :

1. Nutrients
2. Immune cells
3. Lymph
4. Carbon dioxide

02:57

What is Lymph made up of?

06:09

Give any 3 functions / role of Lymphatic system

Popliteal nodes 

Pelvic Lymph Nodes 

Axillary Lymph nodes 

Spleen 

Inguinal Lymph Nodes 

Thymus Glands 

Lymph Vessels 

Payer's Patches (Lacteals)

Thoracic Duct 

Supratrochlear nodes

Lumbar Lymph Nodes 

Tonsils 

Cervical Lymph Nodes

Where can the popliteal node be found.

Where can the inguinal nodes be found?

Introduction to the Lymphatic System

The lymphatic system is a network of tissues and organs that help rid the body of toxins, waste, and other unwanted materials.

Consists of : The spleen, thymus gland, tonsils, lymph glands, and lymph vessels are key components of the lymphatic system

Function of Lymph Nodes & Vessels 

Lymph nodes : Axillary, abdominal, inguinal, popliteal, and supratrochlear play crucial roles in filtering lymph and trapping harmful substances.

Valves within lymph vessels help prevent the backflow of lymph, ensuring its unidirectional flow.

Video: Lymphatic System Function

Watch a short educational video illustrating the formation of Lymph with function and importance of the lymphatic system.

Importance of the Lymphatic System

Highlight the crucial role of the lymphatic system in 

1) Maintaining fluid balance

2) Immune function

3) Waste removal

How does the lymphatic system maintain fluid balance?

What type of cells primarily fight infections
(more than one answer may be correct)?

1. Platelets
2. White blood cells
3. Lymphocytes
4. Red blood cells

Which organ filters lymph fluid?

1. Lymph nodes
2. Heart
3. Liver
4. Kidneys

Malfunctioning of Lymphatic System 

Disruption or dysfunction of the lymphatic system can lead to diseases such as autoimmunity, severe combined immune deficiency, allergies, With Diseases like

1) lymphadenitis

2)  lymphoedema and 

3) Hodgkin’s lymphoma.

Make some notes from the next few slides on the 3 main diseases above.

Lymphadenitis

lymph glands (nodes) become swollen as a result of infection.

The number of microbes that are collected from tissue fluid and circulate in the lymph vessels and then pass through the 

lymph nodes may be too large for the macrophages in the nodes to ingest. This causes the nodes to become infected, enlarged and tender.

Usually the swelling subsides with treatment (antibiotics to combat bacterial infection)

but in some cases lymphadenectomy (removal of the infected lymph nodes, such as

tonsils or adenoids) is carried out.

Glandular fever is an acute infection caused by the Epstein-Barr virus. Symptoms include:

▸ fever                                                        ▸ abnormal lymphocytes

▸sore throat                                             ▸ enlarged liver and spleen.

▸ swollen lymph glands

Lymphoedema

This is where lymph vessels are obstructed and tissue fluid cannot be sufficiently drained from tissues. It leads to oedema.

Causes

The causes of lymphoedema could be the following.

▸ Hereditary lymphoedema is caused by chronic lymphatic obstruction.

▸Women can suffer bouts of lymphoedema during menstruation or pregnancy.

▸Obesity or prolonged standing.

▸Tumours that obstruct lymph vessels.

▸Elephantiasis is caused by filarial worm infection where the parasitic worms block

the lymph vessels.

Lymphoedema

Secondary Causes:  surgery for removal of lymph vessels during mastectomy (breast removal).

Treatments

Lymphoedema has no cure. However, lymph drainage from the extremities can be improved if the patient:

▸sleeps with the foot of the bed elevated to 10–20 cm

▸ wears elastic stockings

▸takes regular moderate exercise

▸avoids spicy or salty foods

▸lightly massages the limbs in the direction of the lymph flow

▸takes diuretics (drugs that increase urination and therefore loss of body fluid).

In severe cases, lymph vessels may be surgically removed.

Hodgkin’s lymphoma

This is a malignant (cancerous) disorder. Lymphocytes either divide abnormally or

fail to die. They build up in lymph nodes which then enlarge due to the tumours.

This usually occurs first in the lymph nodes of the neck region and there is no pain.

Other lymph nodes may be affected (see Figure 8.15). The spleen gets bigger and

the macrophages become abnormal, containing many lobed nuclei and prominent

nucleoli. symptoms include:▸

▸ weight loss

▸ night sweats and fever

▸ anaemia

▸ an abnormal increase in the number of circulating white blood cells, by a factor of 100.

Hodgkin’s lymphoma

Diagnosis involves identifying a cell called Reed-Sternberg in lymphoma as seen under a microscope. 

Treatment involves

- chemotherapy and sometimes radiotherapy as well.

-The cure rate is quite high.

This disease usually affects people between the ages of 15 and 35 years of age but it can affect older people. 

Close relatives of a patient with Hodgkin’s lymphoma have a

1–3 times increased risk of also developing the disease, which suggests an underlying genetic mechanism.

Lymphatic diseases 

Now add some details to the next slide using the notes you have made on the 3 lymphatic diseases we have learnt about.  This can be bullet points to fit in the details such as causes and treatments.

Lymphatic diseases

Write down 3 things you learned in this lesson.

Have students enter three things they learned in this lesson. With this they can indicate their own learning efficiency of this lesson.

Write down 2 things you want to know more about.

Here, students enter two things they would like to know more about. This not only increases involvement, but also gives them more ownership.

Ask 1 question about something you haven't quite understood yet.

The students indicate here (in question form) with which part of the material they still have difficulty. For the teacher, this not only provides insight into the extent to which the students understand/master the material, but also a good starting point for the next lesson.