Lymphatic System Assignment 2- Chantelle McClellan
Pass 3
Introduction
The Lymphatic system is a network of vessels connected to lymphatic organs that
drain lymph from the tissues into the blood. These lymphatic organs include thymus,
lymph nodes, spleen and tonsils. 1 It’s function is to protect the body and act as an
immune defence. It produces white blood cells that protect the body from infections
and diseases 2 and works alongside the immune system.
The lymphatic system consists of blood cells called lymphocytes. Lymphocytes can
defend the body against infection as it can recognise the body’s cells compared to
the foreign ones.
1 Oxford Dictionary
2 Newcastle College
,Primary and secondary lymphatic organs
The primary lymphatic organs refer to organs in which lymphocytes form and mature.
They provide the environment for stem cells to differentiate into T and B cells
whereas the secondary lymphatic organs refer to organs that use the lymphocytes (B
and T cells) and adapt the immune response.
Primary organs include: Bone marrow and thymus
Secondary organs include: Lymph nodes, spleen and tonsils.
3
Structure and function of primary and secondary organs
Structure Location and Function
Thymus Location: The Thymus is located in the
neck of the vertebrae in between your
Has 2 lobes and is shaped like a bow- lungs. It matures the T cells which
tie. Each lobe is covered in a connective detect pathogens and invade them.
tissue capsule and is subdivided into
smaller lobules. Each lobule has a Function:
central medulla and peripheral cortex.
The cortex contains lymphocyte cells. T cells mature in the thymus where they
The medulla contains epithelial cells, are then educated. T cells that contain
some lymphocytes and thymic receptors for self antigens, or do not
corpuscles that make chemical contain any receptors are destroyed.
messengers. This lowers the risk of autoimmune
diseases.
The second function of the thymus is
that it secretes various hormones that
help with the maturing and reproduction
of T cells.
How is structure and function linked?
The thymus consists of a medulla and a
cortex. The T cells, which help fight off
infections, are matured within the
medulla.
4
3 https://en.wikipedia.org/wiki/Lymphatic_system
4 Wikipedia
, Spleen Location:
5
The spleen is the largest lymphatic Found in your abdomen under your rib
organ it is an oval shape organ, it is cage one the left side between your
about the size of your fist. Covering the stomach and diaphragm.
spleen is a capsule of dense connective
tissue and some smooth muscle fibres.
Covering the capsule is a membrane Function:
that is similar to peritoneum.
Inside is lymphatic tissue and red pulp The spleen has multiple functions
( spaces filled with blood.) including extracting old and defective
blood cells and breaking them down,
There are two main blood vessels within removing foreign matter from the blood (
the spleen the splenic artery and the bacteria, viruses and toxins) and stores
splenic vein taking from and too the blood platelets. Another role that
spleen. happens here is the division of
lymphocytes by mitosis that is used to
mount an immune response.
In the foetus and in adults with bone
marrow disease the spleen also plays
an important role in making new
erythrocytes (red blood cells.)
How is structure and function linked?
Inside the red pulp of the spleen is white
pulp which is responsible for where
lymphocytes divide by mitosis.The
general structure of the spleen allows
erythrocytes from the circulation.
Bone Marrow Location:
Bone marrow is made from Found in the centre of bones
hematopoietic cells, marrow adipose
tissue, and stromal cells and is a spongy Function: Bone marrow makes blood
substance. cells such as red blood cells , platelets
and lymphocytes including t and b cells.
How is structure and function linked?
Bone marrow is made up of
hematopoietic cells which is important
5 Wikipedia
Pass 3
Introduction
The Lymphatic system is a network of vessels connected to lymphatic organs that
drain lymph from the tissues into the blood. These lymphatic organs include thymus,
lymph nodes, spleen and tonsils. 1 It’s function is to protect the body and act as an
immune defence. It produces white blood cells that protect the body from infections
and diseases 2 and works alongside the immune system.
The lymphatic system consists of blood cells called lymphocytes. Lymphocytes can
defend the body against infection as it can recognise the body’s cells compared to
the foreign ones.
1 Oxford Dictionary
2 Newcastle College
,Primary and secondary lymphatic organs
The primary lymphatic organs refer to organs in which lymphocytes form and mature.
They provide the environment for stem cells to differentiate into T and B cells
whereas the secondary lymphatic organs refer to organs that use the lymphocytes (B
and T cells) and adapt the immune response.
Primary organs include: Bone marrow and thymus
Secondary organs include: Lymph nodes, spleen and tonsils.
3
Structure and function of primary and secondary organs
Structure Location and Function
Thymus Location: The Thymus is located in the
neck of the vertebrae in between your
Has 2 lobes and is shaped like a bow- lungs. It matures the T cells which
tie. Each lobe is covered in a connective detect pathogens and invade them.
tissue capsule and is subdivided into
smaller lobules. Each lobule has a Function:
central medulla and peripheral cortex.
The cortex contains lymphocyte cells. T cells mature in the thymus where they
The medulla contains epithelial cells, are then educated. T cells that contain
some lymphocytes and thymic receptors for self antigens, or do not
corpuscles that make chemical contain any receptors are destroyed.
messengers. This lowers the risk of autoimmune
diseases.
The second function of the thymus is
that it secretes various hormones that
help with the maturing and reproduction
of T cells.
How is structure and function linked?
The thymus consists of a medulla and a
cortex. The T cells, which help fight off
infections, are matured within the
medulla.
4
3 https://en.wikipedia.org/wiki/Lymphatic_system
4 Wikipedia
, Spleen Location:
5
The spleen is the largest lymphatic Found in your abdomen under your rib
organ it is an oval shape organ, it is cage one the left side between your
about the size of your fist. Covering the stomach and diaphragm.
spleen is a capsule of dense connective
tissue and some smooth muscle fibres.
Covering the capsule is a membrane Function:
that is similar to peritoneum.
Inside is lymphatic tissue and red pulp The spleen has multiple functions
( spaces filled with blood.) including extracting old and defective
blood cells and breaking them down,
There are two main blood vessels within removing foreign matter from the blood (
the spleen the splenic artery and the bacteria, viruses and toxins) and stores
splenic vein taking from and too the blood platelets. Another role that
spleen. happens here is the division of
lymphocytes by mitosis that is used to
mount an immune response.
In the foetus and in adults with bone
marrow disease the spleen also plays
an important role in making new
erythrocytes (red blood cells.)
How is structure and function linked?
Inside the red pulp of the spleen is white
pulp which is responsible for where
lymphocytes divide by mitosis.The
general structure of the spleen allows
erythrocytes from the circulation.
Bone Marrow Location:
Bone marrow is made from Found in the centre of bones
hematopoietic cells, marrow adipose
tissue, and stromal cells and is a spongy Function: Bone marrow makes blood
substance. cells such as red blood cells , platelets
and lymphocytes including t and b cells.
How is structure and function linked?
Bone marrow is made up of
hematopoietic cells which is important
5 Wikipedia
