meso-, mes-, mesi-
(Greek: middle, intermediate; close to a center line; between)
The vertebrate brain is in all of the brain systems that are found in mammals and occur in birds, reptiles, and amphibians, as well as in fish and sharks.
2. The part of the brain developed from the middle cerebral vesicle (hollow organ in the body containing fluid) and consisting of the tectum (part in the body that forms a covering; especially, the back upper section of the midbrain) and cerebral peduncles (neurons joining different parts of the brain), and traversed by the cerebral aqueduct.
The cerebral aqueduct is a narrow opening in the brain that connects the third ventricle with the fourth ventricle, allowing cerebrospinal fluid to flow between these two areas.
Ventricles are openings in the brain that provide a pathway for cerebrospinal fluid is the cushiony fluid that protects the brain and spine from trauma.
The cerebral aqueduct drains cerebrospinal fluid from the third ventricle to the fourth ventricle where the third ventricle is a narrow, four-sided, irregularly shaped opening in the middle of the brain.
The fourth ventricle is a wide, flat open space located in the back bottom part of the brain.
A reference to the interaction between the mesenchymal and epithelial components (tissue that forms a thin protective layer on exposed bodily surfaces and forms the lining of internal cavities, ducts, and organs) in the development of the pancreas, skin, liver, salivary glands, lungs, and other bodily organs.
2. The part of the embryonic mesoderm, consisting of loosely packed, unspecialized cells set in a gelatinous ground substance, from which connective tissue, bone, cartilage, and the circulatory and lymphatic systems develop.
3. Etylmology: from Greek meso-, "middle, between" + Greek enchyma, "infusion"; from en-, "in, into" + Greek chymos, "juice"; from cheein, "to pour, to spill".
The term mesenchyme was introduced into embryology by the German embryologists Oskar Hertwig (1849-1922) and his brother Richard (1850-1937) in 1881.
The peritoneum is the smooth transparent membrane that lines the abdomen and doubles back over the surfaces of the internal organs to form a continuous container or sac.
2. Pertaining to the mesentery which is a membranous fold attaching various organs to the body wall; such as, a fatty membrane placed in the middle of the intestines, and to which they are attached.
This prevents them from becoming entangled with each other by convolutions (coiling or twisting or winding together).
2. The middle section of the embryonic intestine, which develops into the stomach, small intestine, and most of the large intestine.
3. The middle portion of the digestive tract of certain invertebrates; such as, arthropods, lined with an enzyme-secreting tissue and serving as the main site of digestion and absorption.
2. Etymology: from Greek mesenterion, from mesos, "middle" + entern, "intestine".