Lymphatic System - Lecture 10 (Part 2) (COMPLETE)

Question 1

What does lymph transport?

Answer 1

Tissue fluid – Included within that is white blood cells, fats and fat soluble vitamins and plasma proteins.

Question 2

Name TWO ducts that lymphatic vessels drain into.

Wish is the one that drains most of the body?

Answer 2

Lymphatic duct and thoracic duct.

The lymphatic duct on the right only drains a small amount.

The thoracic duct on the left drains the majority.

Question 3

List TWO functions of the lymphatic system.

Answer 3

Immunity against harmful organisms

Return proteins, lipids and water from the interstitial (tissue) fluid to the blood

Question 4

Name FOUR components of the lymphatic system.

Answer 4

• Lymph Fluid (lymph)
• Lymph vessels that the fluid moves through
• Lymph nodes – filtering stations positioned along the vessels
• Lymph organs – spleen and thymus
• Lymphoid tissue - MALT and GALT tissue we find in nasopharynx, tonsils, appendix etc
• Bone marrow because it is where lymphocytes are made

Question 5

Name THREE components (not water) in lymph.

Answer 5

• Plasma proteins
• Leukocytes
• Fats absorbed from the small intestine
• Bacteria and cell debris from damaged tissue

Question 6

Describe specifically the main difference between the lymphatic system and the cardiovascular system.

Answer 6

The lymphatic system is a linear system starting with the blind ended open tubes in the tissue and ending with the tipping of the cleaned lymph into the lymphatic or thoracic duct where it rejoins the circulation system

The cardiovascular system is a circular and closed system in which the fluid (blood) leaves from and returns to the heart

Question 7

Explain the similarities in structure between a lymphatic vessel and a vein.

Answer 7

The lymphatic system has thin walled vessels that resemble veins and follow the same pathways. They have three layers like veins and they have valves like veins to ensure a one way system.

Question 8

Describe the function of lymph nodes.

Answer 8

Lymph nodes are filtering stations. They filter lymph. White blood cells remove foreign matter such as microbes, cell debris and tumour cells.

Question 9

Name TWO immune cells found in lymph nodes.

Answer 9

Macrophages destroy foreign substances by phagocytosis

Lymphocytes destroy the remainder of foreign substances by immune response

Question 10

10. Complete the following:

Lymph enters the ___________ vessels. Foreign substances are trapped in irregular channels by ___________ fibres. ___________ destroy foreign substances by phagocytosis. Whilst ___________ remainder by immune response. Filtered lymph leaves via ___________ vessels. Many ___________ vessels, very few ___________ vessels in turn slow down the flow of ___________.

Answer 10

Lymph enters the AFFERENT vessels. Foreign substances are trapped in irregular channels by RETICULAR fibres. MACROPHAGES destroy foreign substances by phagocytosis. Whilst LYMPHOCYTES destroy remainder by immune response. Filtered lymph leaves via EFFERENT vessels. Many AFFERENT vessels, very few EFFERENT vessels in turn slow down the flow of LYMPH.

Question 11

Name TWO locations containing lymph nodes.

Answer 11

We have lymph nodes all our body but there are five locations that contain many.

Cervical in the neck
Auxiliary the armpit
Mesentric (intestinal)
Vertebral column
Inguinal in the groin

Question 12

Explain the difference between ‘red pulp’ and ‘white pulp’ found in the spleen.

Answer 12

Red pulp contains all the components of the circulating blood. A high amount of circulating blood.

White pulp contains lymphocytes and macrophages.

Question 13

List TWO functions of the spleen.

Answer 13

It is the largest lymph organ.

• Haematopoiesis in foetus because bone marrow is not yet mature enough to produce blood cells
• Blood reservoir
• It is the graveyard of the red blood cell, taking out damaged erythrocytes at the end of their useful life through phagocytosis
• Immunity – T and B Lymphocytes

Question 14

When a spleen is ruptured, explain why it should be removed?

Answer 14

It has a large volume of blood in it because it is a blood reservoir and therefore damage can cause significant haemorrhage and lead to death.

Question 15

15. Name ONE body location that can take over the function of the spleen following removal.

Answer 15

The Liver and red bone marrow can take over some of the function. It is not as efficient but it will do the job. Immune function will be compromised.

Question 16

Describe how T-lymphocytes mature in the body

Answer 16

Epithelial cells produce THYMOSIN which promotes the MATURATION OF T- LYMPHOCYTES [produced in the red bone marrow].

The thymus is where T lymphocytes learn to tell the difference between self and non self. Only one to 5% will pass this test. Those that don’t pass will go through apoptosis and those that do pass leave the thymus via the blood and migrate to lymph nodes and other lymphatic tissues where they colonise

Question 17

State ONE function of the Thymus

Answer 17

It is an organ of the Lymphatic system. It plays an important role in immune development and antibody production in early life.

It is very important in the maturation of T-Lymphocytes. Epithelial cells produce THYMOSIN which promotes the MATURATION OF T- LYMPHOCYTES [produced in the red bone marrow].The thymus is where the T-Lymphocyes (named T for Thymus) learn to differentiate between self and non self.

Question 18

At what age does the thymus start to atrophy?

Answer 18

Atrophy begins at puberty – around the age of 12

Question 19

Define Malt

Answer 19

Mucosa Associated Lymphatic Tissue

It is the first line of immune defence. Small aggregations of lymphoid tissue found in the areas of the body exposed to the external environment. MALT tissues allow our immune system to constantly sample our digestive contents assessing threats and learning what is normal and safe in our environment

Question 20

Name TWO body locations where MALT is located.

Answer 20

Adenoids (aka naso pharyngal tonsils)
Tonsils
Small intestine and large intestine

Question 21

Explain how the lymphatic system plays a role in tissue drainage.

Answer 21

Tissue drainage is the main but not only function of the lymphatic system (the other two are absorption an immunity).
We always accumulate a certain amount of fluid in the tissues because of the high pressure at which blood arrives in the tissue. Some of the fluid and nutrients are forced out of the capillary’s into the interstitial fluid. Interstitial fluid contributes to the nourishment of all of our tissues but 90% of it is returned to the veins via the lymphatic system.

Therefore we need a drainage system to take that fluid, clean it, and return it to the circulation. That drainage system is the lymphatic system. The blind end tubes are an overflow system for fluid and along the way it is cleaned by multiple lymph nodes.

Question 22

Explain how the lymphatic system plays a role in absorption.

Answer 22

Blind end lymphatic capillaries called lacteals are inside each of the villi of the small intestine. Their job is to absorb digested fats and fat soluble vitamins A. D, E and K so that they can be transported around the body.

Question 23

Name TWO factors that contribute to lymphatic fluid drainage

Answer 23

Lymphatic fluid is drained with the assistance of the following:

Lymphatic pump - mild rhythmical contractions of the lymphatic vessels. This is similar to peristalsis. It helps to keep the lymph propelling in the right direction and the valves and lymph vessels prevented from flowing the wrong way

skeletal muscle pump - Our skeletal muscles push lymph through the lymph vessels. Movement and exercise drains fluid, especially from the calf muscles.

Respiratory pump - when we breathe properly we create a vacuum in our thoracic cavity that helps to suck lymph back towards the heart. Lymph moves from high to low pressure

Question 24

Using definitions, explain the difference between ‘lymphangitis’ and ‘lymphadenitis’.

Answer 24

Lymphangitis: Lymph+angio+itis meaning Lymph-vessel-inflammation

Inflammation of the lymph vessels, characterised by the red line following the line of the lymph vessels from the point of inflammation. It is a bacterial infection. Usually Streptococcus.

Lymphadentis: Lymph+adeno+itis meaning Lymph-gland (or in this case node)-inflammation

Inflammation of the lymph nodes. Usually a bacterial infection

Question 25

Explain why lymphangitis can lead to septicaemia.

Answer 25

The infection can spread from the lymph to the blood because the lymphatic system enters in to the venous system

Question 26

Name ONE characteristic sign / symptom of lymphangitis

Answer 26

Swelling, with a painful red line below the skin surface that is moving along the line of the lymph vessel.

Fever, malaise, muscle ache, low appetite

Question 27

Explain why protein accumulation occurs in lymphoedema

Answer 27

Lymphoedema refers to a build up of fluid in lymphatic vessels. It is due to a compromised lymphatic system leading to reduced lymphatic return.

Obstruction of a lymph vessel causes an increase in protein accumulation in the interstitial fluid which is not being carried away by the lymph vessels.

Question 28

Explain the key difference between ‘Stage one’ and ‘Stage two’ lymphoedema.

Answer 28

Stage 1: Pitting Oedema – This is the water retention phase leading to swelling of the soft tissue. Press your finger into it and it leaves a dent. It doesn’t spring back

Stage 2: Fibrosis of vessels - inflammation and activation of fibroblasts leading to damage to the vessels

Question 29

List TWO signs / symptoms of lymphoedema.

Answer 29

Heavy, painful, swollen are with pitting - Press your finger into it and it leaves a dent. It doesn’t spring back

Severe fatigue of affected area

Discolouration of the skin overlying the lymphoedema

Recurring skin infections in the affected limb which may lead to thickening and hardening of the overlying skin

Question 30

Name ONE primary and ONE secondary cause of lymphoedema

Answer 30

Primary cause: congenital, poorly developed lymphatic vessels new paragraph Secondary cause: damage to the lymphatic system caused by radiotherapy, lymph node removal, infection

Question 31

Name ONE sign / symptom more suggestive of lymphadenitis.

Answer 31

Inflammation of the lymph nodes. Usually a bacterial infection. Often following a sore throat.

Enlarged lymph nodes that are often painful on palpation

Question 32

State TWO causes of Splenomegaly

Answer 32

To answer this, think of what the spleen does. Involves in immunity.

• Haemolytic anaemias such as thalassaemia and sickle cell anaemia because the spleen needs to deal with more blood cells than usual and increases in size to do so.
• Liver disease because the spleen is connected to the portal vein and therefore poral vein hypertension could be a cause.
• Viral of Bacterial infections because of the spleen’s role in immunity
• Blood/Lymphatic malignancies such as Leukaemia and Hodgkins lymphoma due to excess production of white blood cells.

Question 33

Name ONE infectious cause of splenomegaly.

Answer 33

Glandular fever

Question 34

1Name ONE pathology for each of the following. that may cause splenomegaly:

a. Liver disease?

b. Blood / lymphatic malignancy?

c. Haemolytic anaemia?

Answer 34

a. Liver disease?
Cirrhosis leading to portal vein hypertension

b. Blood / lymphatic malignancy?
Leukaemia and Hodgkin’s lymphoma due to excess production of white blood cells

c. Haemolytic anaemia?
Thalassaemia and sickle cell anaemia due to excess need to remove damaged or malformed red blood cells.

Question 35

List TWO signs / symptoms of splenomegaly

Answer 35

• Abdominal pain
• Early SATIETY due to less space for the stomach
• Symptoms of Haemolytic anaemia due to accompanying cytopenia. This is because as the spleen enlarges, it uses more circulating blood, taking it from elsewhere in the body.
• Palpable left upper quadrant abdominal mass

Question 36

Explain specifically how the following factors can optimise lymphatic health:

a. Exercise

b. Removing common allergens

c. High anti-inflammatory and anti-oxidant diet.

Answer 36

a. Exercise
Lymphatic vessels rely on exercise to pump lymph through the body through skeletal muscle contraction.

Jumping on a trampoline is a very good option

b. Removing common allergens

Allergens stimulate the release of histamine which contributes to swelling.
Removing common allergens from the diet reduces the stress on the digestive and immune systems

c. High anti-inflammatory and anti-oxidant diet.
Green leafy vegetables, berries amid 3 foods, nuts and seeds, tumeric, ginger. This reduces inflammation and helps to mitigate oxidative stress

*Dry Brushing is also helpful