Lymphatic System Lecture Notes

These flashcards cover the lymphatic system's functions, structures, clinical cases related to lymphatic health, and responses to various conditions.

What is the main function of the lymphatic system?

To return interstitial fluid and proteins to the vascular compartment.

What do lymph vessels return to the circulatory system?

White blood cells and leaked proteins.

How do white blood cells navigate in lymphatic flow?

They use amoeboid mobility to escape blood vessels and travel through lymph.

What substance is transported by the lymphatic system from the digestive tract?

Fats, in the form of chylomicrons.

What significant role does the lymphatic system play regarding interstitial fluids?

It controls the concentration of proteins, volume, and pressure of interstitial fluids.

Where do lymph vessels from the lower part of the body empty into?

The thoracic duct.

Where does lymph from the right side of the body drain?

Into the right lymph duct.

What is the structure that surrounds lymph nodes?

A connective tissue capsule.

What is the typical length of a lymph node?

Less than 2.5 cm.

What are the three regions where lymph nodes tend to cluster?

Inguinal, axillary, and cervical nodes.

What do the lymph nodules in lymph nodes contain?

Lymphocytes and macrophages.

How does the afferent lymphatic vessel function in lymph nodes?

It carries lymph into the node from different parts of its periphery.

What mechanism aids in the flow of lymph through the lymphatic system?

Intrinsic intermittent contraction of lymphatic vessels.

What generally causes lymph flow to increase?

Elevated interstitial fluid pressure.

What can compress lymph vessels externally to stimulate lymph flow?

Contraction of skeletal muscles, movement, or external compression.

What is the lymphatic system mainly composed of?

Lymphatic vessels and nodes.

What are sentinel lymph nodes?

The first lymph nodes that absorb dye or tracer during breast cancer surgery.

What is the main purpose of a sentinel lymph node biopsy?

To determine if breast cancer has spread.

What helps to prevent lymphedema after lymph node dissection?

Physical therapy that includes exercises and massage.

What could cause enlarged lymph nodes in inguinal swelling?

Infection or cancer in lower extremities.

What is the primary role of the spleen?

To filter blood and respond to pathogens.

What type of tissue comprises the spleen?

White pulp and red pulp.

How does the spleen respond to an emergency situation such as hemorrhage?

By contracting smooth muscle to squeeze out blood into circulation.

Where are tonsils located?

Under the mucous membranes of the nose, mouth, and throat.

What is the primary function of the thymus?

Processing and maturation of T-lymphocytes.

What hormone does the thymus produce?

Thymosin.

How does the lymphatic system assist in protein reabsorption?

By returning leaked proteins to the blood circulation from the interstitium.

What happens to proteins that leak out of capillaries?

They cannot be reabsorbed back into the bloodstream due to various pressure gradients.

What is a primary risk factor for lymphedema?

Increased capillary blood pressure.

What is edema?

An accumulation of fluid in the tissues.

How does exercise affect risk of lymphedema?

It decreases the risk by enhancing lymphatic flow.

What is the average daily flow of lymph through the thoracic duct?

About 2 to 3 liters per day.

How do lymphatic capillaries differ from blood capillaries regarding permeability?

Lymphatic capillaries allow large particles like proteins to enter.

What aids lymphatic capillary function?

Valves and anchoring filaments that assist in absorbing interstitial fluid.

What happens when intravascular pressure exceeds interstitial pressure?

Lymph flow increases significantly.

What role do lymph nodes play in the lymphatic system?

They filter lymph before it returns to the blood.

What is lymph?

Fluid that forms when interstitial fluid enters the lymphatic system.

Where does lymph from the left breast and parts of the chest drain?

Into the thoracic duct.

How do macrophages contribute to lymphatic function?

By engulfing debris and pathogens in lymphatic tissues.

What is the primary method of lymph transport?

Contraction of surrounding skeletal muscles and valves compression.

Why is lymph flow minimal at negative interstitial pressures?

Because pressure gradients are not favorable for lymph movement.

What is one significant consequence of lymphatic obstruction?

Increased risk of edema and lymphedema.

What does a positive sentinel node indicate?

Possible metastasis of cancer to lymph nodes.

What is the general anatomical location of the spleen?

Upper left abdominal cavity.

What types of cells are predominantly found in white pulp of the spleen?

Lymphocytes.

What can result from injury to lymphatic vessels?

Accumulation of lymph and lymphedema.

What is a unique feature of lymphatic capillaries?

They have overlapping endothelial cells that act as valves.

What contributes to the maintenance of lymph flow within the lymph nodes?

Valves that prevent backflow.

How do lymph nodes help the immune system?

By filtering lymph and facilitating immune responses.

What is the risk associated with axillary lymph node dissection post-mastectomy?

Development of lymphedema.

What are the two main types of lymphatic tissues in the spleen?

White pulp and red pulp.

What is the primary function of tonsils?

To provide protection against pathogens entering through the air or food.

What can lead to increased lymphatic flow?

Exercises that enhance skeletal muscle contraction.

How does body movement influence lymphatic return?

It aids in pumping lymph back into the venous system.

What is the relationship between lymphatic vasculature and muscle activity?

Muscle contraction promotes lymph flow through vascular compression.

What effect does aging have on the thymus?

It decreases in size and function after puberty.

How do sentinel lymph nodes function in breast cancer detection?

By identifying the first nodes likely to hold cancer cells.

What condition affects the immune response in patients who have undergone lymph node dissection?

Decreased immune surveillance and higher susceptibility to infections.

What is indicated by swelling of lymph nodes?

Possible infection or malignancy within the region they drain.