Random musings of an anatomist turned medical student.
Restoration of excess interstitial fluid and proteins to the blood Absorption of fats and fat-soluble vitamins from the digestive system and transport of these elements to the venous circulation Defense against invading organisms [ 1234 ] Next: Gross Anatomy Lymph Lymph is a fluid derived from blood plasma.
It is pushed out through the capillary wall by pressure exerted by the heart or by osmotic pressure at the cellular level.
Lymph contains nutrients, oxygen, and hormones, as well as toxins and cellular waste products generated by the cells. As the interstitial fluid accumulates, it is picked up and removed by lymphatic vessels that pass through lymph nodes, which return the fluid to the venous system.
As the lymph passes through the lymph nodes, lymphocytes and monocytes enter it. At the level of the gastrointestinal GI tract, lymph has a milky consistency that is Describe the gross anatomy of the to fatty acids, glycerol, and rich fat content.
Lacteals are lymph vessels that transport intestinal fat and are localized to the GI tract. They are arranged in an overlapping pattern, so that pressure from the surrounding capillary forces at these cells allows fluid to enter the capillary see the image below.
The lymphatic capillaries coalesce to form larger meshlike networks of tubes that are located deeper in the body; these are known as lymphatic vessels.
Lymph capillaries in spaces. Blind-ended lymphatic capillaries arise within interstitial spaces of cells near arterioles and venules.
View Media Gallery The lymphatic vessels grow progressively larger and form 2 lymphatic ducts: Like veins, lymphatic vessels have 1-way valves to prevent any backflow see the image below.
The pressure gradients that move lymph through the vessels come from skeletal muscle action, smooth muscle contraction within the smooth muscle wall, and respiratory movement. View Media Gallery Lymph nodes Lymph nodes are bean-shaped structures that are widely distributed throughout the lymphatic pathway, providing a filtration mechanism for the lymph before it rejoins the blood stream.
The average human body contains approximately of them, predominantly concentrated in the neck, axillae, groin, thoracic mediastinum, and mesenteries of the GI tract. Lymph nodes constitute a main line of defense by hosting 2 types of immunoprotective cell lines, T lymphocytes and B lymphocytes.
Lymph nodes have 2 distinct regions, the cortex and the medulla. The cortex contains follicles, which are collections of lymphocytes. At the center of the follicles is an area called germinal centers that predominantly host B-lymphocytes while the remaining cells of the cortex are T-lymphocytes.
Vessels entering the lymph nodes are called afferent lymphatic vessels and, likewise, those exiting are called efferent lymphatic vessels see the image below. View Media Gallery Extending from the collagenous capsule inward throughout the lymph node are connective tissue trabeculae that incompletely divide the space into compartments.
Deep in the node, in the medullary portion, the trabeculae divide repeatedly and blend into the connective tissue of the hilum of the node. Thus the capsule, the trabeculae, and the hilum make up the framework of the node.
Within this framework, a delicate arrangement of connective tissue forms the lymph sinuses, within which lymph and free lymphoid elements circulate. A subcapsular or marginal sinus exists between the capsule and the cortex of the lymph node. Lymph passes from the subcapsular sinus into the cortical sinus toward the medulla of the lymph node.
Medullary sinuses represent a broad network of lymph channels that drain toward the hilum of the node; from there, lymph is collected into several efferent vessels that run to other lymph nodes and eventually drain into their respective lymphatic ducts see the image below.
View Media Gallery Thymus The thymus is a bilobed lymphoid organ located in the superior mediastinum of the thorax, posterior to the sternum. After puberty, it begins to decrease in size; it is small and fatty in adults after degeneration.Since , iridis-photo-restoration.com has provided high quality information about health, wellness, and the science behind the human body.
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Explore the anatomy systems of the human body! Sep 19, · The lymphatic system is unique, in that it is a 1-way system that returns lymph fluid via vessels to the cardiovascular system for eventual elimination of toxic byproducts by end organs, such as the kidney, liver, colon, skin, and lungs.
Gross Anatomy. Lymph. Lymph is a fluid derived from blood plasma. It is pushed out through. Apr 23, · These past couple of weeks have gotten really busy with the end of the semester coming.
Tests have been coming at two per week for the past month, but the good news is that there's only two weeks and four more tests left. Sep 24, · External Genitalia. The vulva, also known as the pudendum, is a term used to describe those external organs that may be visible in the perineal area (see the images below).
ANATOMY ATLASES & IMAGE DATABASES Anatomy Atlases & Image Databases Related Centers. FOR CT, CAT, MRA, MRI, X-RAY, ULTRASOUND ETC. ATLASES SEE THE RADIOLOGY CENTER FOR ANATOMY ATLASES - PATHOLOGY SEE THE PATHOLOGY, FORENSICS & VIROLOGY CENTER: PATHOLOGY CENTER FOR ANATOMY ATLASES - SURGERY SEE THE SURGERY .