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The axillary nodes

The axillary nodes are a group of lymph nodes located in the axillary (or armpit) region of the body. They perform the vital function of filtration and conduction of lymph from the upper limbs, pectoral region, and upper back.

The axillary lymph nodes are a group of twenty to thirty large lymph nodes located in the deep tissues in and around the armpit. These nodes are arranged into five distinct groups: pectoral (anterior), lateral, subscapular (posterior), central (intermediate), and subclavicular (medial). Each group of lymph nodes receives lymph from a specific region of the body or from another group of lymph nodes.

The immune and lymphatic systems of the upper torso

The upper torso contains many important structures of the lymphatic and immune systems including many lymph nodes, the lymphatic ducts, thymus gland, and red bone marrow. These structures work together to perform the vital functions of producing immune responses to deadly pathogens; producing blood cells; transporting lymph and lipids; and filtering contaminants from lymph.

A vast network of lymph nodes and lymphatic vessels spreads throughout the diverse tissues of the upper torso. This lymphatic network performs the vital task of draining interstitial fluid from the tissues of the thorax and returning it to the blood supply. Many lymphatic vessels also carry lymph to the upper torso from the limbs, abdomen, head and neck.

The palatine tonsils

The palatine tonsils are located at the back of the throat. One tonsil is located on the left side of the throat and the other is located on the right side. The tonsils play a role in protecting the body against respiratory and gastrointestinal infections.

The lingual tonsils

The lingual tonsil is a small mound of lymphatic tissue located at the back of the base of the tongue. Two lingual tonsils are in the mouth, one on each side of the tongue. They are composed of lymphatic tissue that functions to assist the immune system in the production of antibodies in response to invading bacteria or viruses. If the tonsils are repeatedly swollen or infected over an extended period of time, they may need to be removed.

The cervical nodes

The cervical nodes are one of the six major locations of lymph nodes. They are grouped along the lower border of the jaw, in front of and behind the ears, and deep in the neck along the larger blood vessels. They drain the skin of the scalp, face, tissues of the nasal cavity, and the pharynx. All lymph nodes have the primary function of the production of lymphocytes, which help defend the body against microorganisms and against harmful foreign particles and debris from lymph before it is returned to the blood stream.

The adenoids (the pharyngeal tonsils)

The adenoids, also known as the pharyngeal tonsils, are a part of the lymphatic system located in the back of the throat and up into the nasal cavity. Much like the tonsils (palatine tonsils), the adenoids are made up of folded lymphatic tissue, lined with epithelial cells, house mucosal glands, and are covered in cilia and mucus. One single such fold is termed an adenoid.

The immune and lymphatic system of the head and neck

The immune and lymphatic system of the head and neck includes the tonsils, several sets of lymph nodes, countless lymphatic vessels, and red bone marrow. All of these structures work together to drain, filter and cleanse the interstitial fluids of the head and neck and destroy harmful pathogens that may infect this region.

The cardiovascular system of the leg and foot

The cardiovascular system of the leg and foot includes all of the blood vessels that provide blood flow to and from the tissues of the lower limb. These blood vessels supply vital oxygen and nutrients to support cellular metabolism in the lower limb while transporting carbon dioxide and metabolic wastes back to the trunk to be removed from the body. Large volumes of deoxygenated blood are stored in the veins of the lower limbs as a reservoir for the rest of the body. Blood flow also helps to maintain the homeostasis of body temperature by delivering hot blood from the trunk to the tissues of the extremities.

The cardiovascular system of the upper limbs

The cardiovascular system of the upper limbs plays the vital role of ensuring the adequate flow of blood to and from the shoulders, arms, hands and fingers. Adequate flow of oxygenated blood to the tissues of the upper limbs is critical to their health through the delivery of oxygen, water, and nutrients. Blood flow also helps to regulate body temperature in this region and reduces the risk of frostbite of the fingers in extreme weather conditions.

Blood filtration in the kidneys

The kidneys filter about one-quarter (750-1000 pints) of the blood that is output by the heart daily. This blood is sent to the body's filter treatment plant, where it is purified by the kidneys and circulated on to the rest of the body. Some of the blood flow becomes fluid waste (1/1000th to 2/1000th) and is sent into the bladder for storage until it can be conveniently expelled. This toxic waste is called urine.