Chapter 14 Flashcards
Any substance or microorganism that causes disease or damage to the tissues of the body
Pathogen
Functions of the lymphatic system
Fluid balance
Lipid absorption
Defense
About 30 liters (L) of fluid pass from the blood capillaries into the interstitial space each day, whereas only 27 L pass from the interstitial spaces back into the blood. If the extra 3 L of interstitial fluid remained in the interstitial spaces, ___ would result, causing tissue damage and death. Instead, 3 L of fluid enters the lymphatic capillaries. Once inside the lymphatic capillaries, this fluid is called ___ and it passes through the lymphatic vessels.
Fluid balance - edema, lymph
Lymph contains solutes derived from 2 sources
- Substances in plasma - ions, nutrients, gases, and some proteins, pass from blood capillaries into the interstitial spaces, and then into lymphatic capillaries to become part of the lymph
- Substances such as hormones, enzymes, and waste products derived from cells within tissues, are also part of the lymph
The lymphatic vessels absorbs lipids and other substances from the digestive tract through lymphatic vessels called ___ located in the lining of the small intestine. Lipids enter the ___ (same) and pass through the lymphatic vessels to the venous circulation. The lymph passing through these lymphatic vessels appears white because of its lipid content and is called ___.
Lipid absorption - lacteal, chyle
Pathogens, such as microorganisms and other foreign substances, are filtered from lymph by ___ and from blood by the ___. In addition, ___ and other cells are capable of destroying pathogens.
Defense - lymph nodes, spleen, lymphocytes
The lymphatic system includes ___. (7)
Lymph, lymphocytes, lymphatic vessels, lymph nodes, tonsils, spleen, and thymus
T/F: The lymphatic system carries fluid in one direction, from tissues to the circulatory system.
T
Tiny, closed-ended vessels consisting of simple squamous epithelium that are more permeable than blood capillaries because they lack a basement membrane and fluid moves easily into them
Lymphatic capillaries
Where are lymphatic capillaries NOT FOUND?
Central nervous system, bone marrow, and tissues lacking blood vessels such as epidermis and cartilage
A ___ of lymphatic capillaries collects excess interstitial fluids from the dermis and subcutaneous tissue and a ___ collects excess fluid from muscle, the viscera, and other deep structures.
Superficial, deep
Three factors cause compression of lymphatic vessels
- Contraction of surrounding skeletal muscle during activity
- Periodic contraction of smooth muscle in lymphatic vessel wall
- Pressure changes in the thorax during breathing
Lymphatic vessels from the right upper limb and the right half of the head, neck, and chest form the ___ which empties into the ___.
Right lymphatic duct, right subclavian vein
Lymphatic vessels from the rest of the body enter the ___ which empties into the ___.
Thoracic duct, left subclavian vein
What are the lymphatic organs? (4)
Tonsils, lymph nodes, spleen, and thymus
It is characterized by housing many lymphocytes and other defense cells such as macrophages.
Lymphatic tissue
The lymphocytes originate from ___ and are carried to the blood by ___.
Red bone marrow, lymphatic organs
Three groups of tonsils
Palayine, pharyngeal, lingual
Located on each side of the posterior opening of the oral cavity; these are the ones usually referred to as the tonsils.
Palatine tonsils
Located near the internal opening of the nasal cavity.
Pharyngeal tonsil
When a pharyngeal tonsil is enlarged, it is commonly called the ___.
Adenoid
Located on the posterior surface of the tongue
Lingual tonsil
Removal of pharyngeal tonsils
Adenoidectomy
Removal of palatine tonsils
Tonsillectomy
