Spleen

Definition

The spleen is an organ located in the upper left part of the abdomen, responsible for filtering blood, recycling iron, and supporting the immune system. It plays a vital role in the body's ability to respond to infections and maintain healthy blood cells, interacting closely with the circulatory and lymphatic systems to perform these functions.

5 Must Know Facts For Your Next Test

1. The spleen can be divided into two main regions: red pulp, which deals with blood filtration and storage, and white pulp, which is involved in immune responses.
2. An adult spleen typically weighs about 150 grams and is approximately 11 centimeters long.
3. The spleen is often referred to as a 'blood reservoir' because it can store a significant amount of blood, which can be released into circulation when needed.
4. In cases of severe infection or other diseases, the spleen can become enlarged, a condition known as splenomegaly.
5. While the spleen is important for immune function, people can live without it; however, they may be more susceptible to infections.

Review Questions

• How does the spleen interact with both the circulatory and lymphatic systems to support immune function?
  • The spleen interacts with the circulatory system by filtering blood to remove old or damaged red blood cells and pathogens. It also plays a key role in the lymphatic system by producing lymphocytes, which are essential for the immune response. This interconnectedness ensures that when pathogens enter the bloodstream, the spleen can quickly mobilize immune cells to respond effectively.
• Discuss how splenomegaly can impact overall health and what underlying conditions might lead to this enlargement.
  • Splenomegaly can lead to various health issues, such as increased susceptibility to infections due to impaired immune function. Conditions like liver disease, certain cancers, or infections such as mononucleosis can cause enlargement of the spleen. By understanding these connections, healthcare providers can better assess a patient's overall health and potential risks associated with an enlarged spleen.
• Evaluate the significance of the spleen's functions in relation to hematopoiesis and its role in the body's defense mechanisms.
  • The spleen's role in hematopoiesis is particularly significant during fetal development when it contributes to the formation of blood cells. In addition to this function, the spleen is vital for immune defense by filtering pathogens and producing lymphocytes. Its dual roles highlight how essential the spleen is not only for maintaining healthy blood but also for ensuring an effective immune response against infections, making it a critical organ in human health.

Related terms

Lymphatic System: A network of tissues and organs that help rid the body of toxins, waste, and other unwanted materials, playing a crucial role in the immune response.

Hematopoiesis:

The process of creating new blood cells in the body, occurring primarily in the bone marrow and the spleen during fetal development.

Red Pulp: A component of the spleen that filters and removes old or damaged red blood cells from circulation, while also serving as a reservoir for blood.