Transcript Lymphatic System and Thyroid Gland

Lymphatic System
and
Thyroid Gland
• Many different organs and systems work together
in an effort to keep us alive and healthy.
• In this ongoing struggle, the lymphatic system
plays a central role; it has an extensive
drainage network that helps to:
- keep bodily fluid levels in balance;
- defends the body against infections, and
- assists in tissue repairs.
The production, maintenance and distribution of
lymphocytes; WHITE BLOOD CELLS (WBCs)
Basic Overview
– The Lymphocytes (WBCs), protect the body against
antigens (viruses, bacteria, etc.) that invade the body.
– Lymphocytes are produced and stored within lymph
organs, such as:
• The spleen,
• The thymus and
• The bone marrow.
Lymphocytes must be specifically made to defend
any new or known invader that enters the body.
• The return of fluid and solutes from the
peripheral tissues of the blood.
– “Lymph” is the liquid that “baths” every cell
in the body. This fluid, called Interstitial Fluid,
is the transport mechanism.
– Lymph Nodes are areas within the body that
collect waste proteins (antigens, broken up
cells) and dispose of them.
The Three Main Components of the
Lymphatic System
• 1. Vessels– A network of lymph vessels (like blood
vessels) start from the peripheral
(outside) tissues and move internally
towards local areas of “holding,
digestive sites” – Lymph Nodes.
• 2. Fluid – LYMPH
– The Lymph is clear and watery. It flows through
the lymphatic vessels.
– Lymph Fluid contains:
• Fluid from the intestines (chyme), which
contains proteins and fats.
• RBCs.
• WBCs, especially lymphocytes, the cells that
attack bacteria in the blood.
• 3. Lymphoid organs– Lymphoid organs are connected to the
lymphatic vessels and contain large numbers
of lymphocytes.
• (Ex. Lymph nodes, spleen and thymus).
– Lymph organs = bone marrow, lymph nodes, spleen,
and thymus.
– Human lymph nodes, called lymph glands and “swollen
glands,” are bean-shaped and range in size from a few
millimeters to about 1-2 cm in their normal state.
– They may become enlarged due to a tumor or
infection. (Where does a doctor check first?)
– White blood cells are located within honeycomb
structures of the lymph nodes.
– Spleen- The spleen, which is located in the upper left
part of the abdomen under the ribcage, works as part
of the lymphatic system to protect the body. It clears
worn out red blood cells and other foreign bodies from
the bloodstream to help fight off infection.
• Tonsils—The tonsils are areas of lymphoid
tissue on either side of the throat.
• Thymus- an organ located in the upper
anterior portion of the chest cavity just
behind the sternum.
• Hormones produced by this organ
stimulate the production of certain infectionfighting cells.
• Through the hormones it produces,
the thyroid gland influences almost
all of the metabolic processes in
your body.
• Thyroid disorders can range from a small,
harmless goiter (enlarged gland) that needs
no treatment to life-threatening cancer.
• The most common thyroid problems involve
abnormal production of thyroid hormones.
• Too much of these vital body chemicals
results in a condition known as
hyperthyroidism.
• Insufficient hormone production leads to
hypothyroidism.
Reinforcement Video