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Trabecula
A trabecula (plural trabeculae, from Latin for "small beam") is a small, often microscopic, tissue element in the form of a small beam, strut or rod that supports or anchors a framework of parts within a body or organ. A trabecula generally has a mechanical function, and is usually composed of dense collagenous tissue (such as the trabecula of the spleen). It can be composed of other material such as muscle and bone. In the heart, muscles form trabeculae carneae and septomarginal trabeculae. Cancellous bone is formed from groupings of trabeculated bone tissue. In cross section, trabeculae of a cancellous bone can look like septa, but in three dimensions they are topologically distinct, with trabeculae being roughly rod or pillar-shaped and septa being sheet-like. When crossing fluid-filled spaces, trabeculae may offer the function of resisting tension (as in the penis, see for example trabeculae of corpora cavernosa and trabeculae of corpus spongiosum) or providing a cell fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trabeculae Carneae
The trabeculae carneae (columnae carneae, or meaty ridges) are rounded or irregular muscular columns which project from the inner surface of the right and left ventricle of the heart.Moore, K.L., & Agur, A.M. (2007). ''Essential Clinical Anatomy: Third Edition.'' Baltimore: Lippincott Williams & Wilkins. 90-94. These are different from the pectinate muscles, which are present in the atria of the heart. In development, trabeculae carneae are among the first of the cardiac structures to develop in the embryonic cardiac tube. Further, throughout development some trabeculae carneae condense to form the myocardium, papillary muscles, chordae tendineae, and septum. Types There are two kinds: * Some are attached along their entire length on one side and merely form prominent ridges, * Others are fixed at their extremities but free in the middle, as in the moderator band in the right ventricle, or the papillary muscles that holds chordae tendinae, which are connected to cusps of valv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trabeculae Of Corpora Cavernosa Of Penis
From the internal surface of the fibrous envelope of the corpora cavernosa penis, as well as from the sides of the septum, numerous bands or cords are given off, which cross the interior of these corpora cavernosa in all directions, subdividing them into a number of separate compartments, and giving the entire structure a spongy appearance. These bands and cords are called the trabeculae of corpora cavernosa of penis, and consist of white fibrous tissue, elastic fibers, and plain muscular fibers. In them are contained numerous arteries and nerves. The component fibers which form the trabeculae are larger and stronger around the circumference than at the centers of the corpora cavernosa; they are also thicker behind than in front. The interspaces (cavernous spaces), on the contrary, are larger at the center than at the circumference, their long diameters being directed transversely. They are filled with blood, and are lined by a layer of flattened cells similar to the endothelial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trabeculae Of Corpus Spongiosum Of Penis
The fibrous envelope of the corpus cavernosum urethrae is thinner, whiter in color, and more elastic than that of the corpora cavernosa penis. It is called the trabeculae of corpus spongiosum of penis. The trabeculae are more delicate, nearly uniform in size, and the meshes between them smaller than in the corpora cavernosa penis: their long diameters, for the most part, corresponding with that of the penis. The external envelope or outer coat of the corpus cavernosum urethrae is formed partly of unstriped muscular fibers, and a layer of the same tissue immediately surrounds the canal of the urethra. See also * Trabeculae of corpora cavernosa of penis From the internal surface of the fibrous envelope of the corpora cavernosa penis, as well as from the sides of the septum, numerous bands or cords are given off, which cross the interior of these corpora cavernosa in all directions, subdividing the ... References Mammal male reproductive system Human penis anatomy { ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trabeculae Of Spleen
The fibroelastic coat of the spleen invests the organ, and at the hilum is reflected inward upon the vessels in the form of sheaths. From these sheaths, as well as from the inner surface of the fibroelastic coat, numerous small fibrous bands, the trabeculae of the spleen (or splenic trabeculae), emerge from all directions; these uniting, constitute the frame-work of the spleen. The spleen therefore consists of a number of small spaces or areolae, formed by the trabeculae; in these areolae is contained the splenic pulp. See also * Spleen * Trabecula A trabecula (plural trabeculae, from Latin for "small beam") is a small, often microscopic, tissue element in the form of a small beam, strut or rod that supports or anchors a framework of parts within a body or organ. A trabecula generally ha ... References Spleen (anatomy) {{Portal bar, Anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trabecular Meshwork Of The Eye
The trabecular meshwork is an area of tissue in the eye located around the base of the cornea, near the ciliary body, and is responsible for draining the aqueous humor from the eye via the anterior chamber (the chamber on the front of the eye covered by the cornea). The tissue is spongy and lined by trabeculocytes; it allows fluid to drain into a set of tubes called Schlemm's canal which is lined by endothelium with blood and lymphatic properties that allow aqueous humor to flow into the blood system. Structure The meshwork is divided up into three parts, with characteristically different ultrastructures: #''Inner uveal meshwork'' - Closest to the anterior chamber angle, contains thin cord-like trabeculae, orientated predominantly in a radial fashion, enclosing trabeculae spaces larger than the corneoscleral meshwork. #''Corneoscleral meshwork'' - Contains a large amount of elastin, arranged as a series of thin, flat, perforated sheets arranged in a laminar pattern; consi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cancellous Bone
A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, and enable mobility. Bones come in a variety of shapes and sizes and have complex internal and external structures. They are lightweight yet strong and hard and serve multiple functions. Bone tissue (osseous tissue), which is also called bone in the uncountable sense of that word, is hard tissue, a type of specialized connective tissue. It has a honeycomb-like matrix internally, which helps to give the bone rigidity. Bone tissue is made up of different types of bone cells. Osteoblasts and osteocytes are involved in the formation and mineralization of bone; osteoclasts are involved in the resorption of bone tissue. Modified (flattened) osteoblasts become the lining cells that form a protective layer on the bone surface. The mineralized matri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cancellous Bone
A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, and enable mobility. Bones come in a variety of shapes and sizes and have complex internal and external structures. They are lightweight yet strong and hard and serve multiple functions. Bone tissue (osseous tissue), which is also called bone in the uncountable sense of that word, is hard tissue, a type of specialized connective tissue. It has a honeycomb-like matrix internally, which helps to give the bone rigidity. Bone tissue is made up of different types of bone cells. Osteoblasts and osteocytes are involved in the formation and mineralization of bone; osteoclasts are involved in the resorption of bone tissue. Modified (flattened) osteoblasts become the lining cells that form a protective layer on the bone surface. The mineralized matri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone
A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provide structure and support for the body, and enable animal locomotion, mobility. Bones come in a variety of shapes and sizes and have complex internal and external structures. They are lightweight yet strong and hard and serve multiple Function (biology), functions. Bone tissue (osseous tissue), which is also called bone in the mass noun, uncountable sense of that word, is hard tissue, a type of specialized connective tissue. It has a honeycomb-like matrix (biology), matrix internally, which helps to give the bone rigidity. Bone tissue is made up of different types of bone cells. Osteoblasts and osteocytes are involved in the formation and mineralization (biology), mineralization of bone; osteoclasts are involved in the bone resorption, resor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Septomarginal Trabecula
The moderator band (also known as septomarginal trabecula) is a band of cardiac muscle found in the right ventricle of the heart. It is well-marked in sheep and some other animals. It extends from the base of the anterior papillary muscle to the ventricular septum. Structure The moderator band is located in the right ventricle. The moderator band connects the base of the anterior papillary muscles to the ventricular septum. Function The moderator band is important because it carries part of the right bundle branch of the atrioventricular bundle of the conduction system of the heart to the anterior papillary muscle. This shortcut across the chamber of the ventricle ensures equal conduction time in the left and right ventricles, allowing for coordinated contraction of the anterior papillary muscle. Clinical significance The moderator band is often used by radiologists and obstetricians to more easily identify the right ventricle in prenatal ultrasound. History From its at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteoporosis
Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to bone fragility, and consequent increase in fracture risk. It is the most common reason for a broken bone among the elderly. Bones that commonly break include the vertebrae in the spine, the bones of the forearm, and the hip. Until a broken bone occurs there are typically no symptoms. Bones may weaken to such a degree that a break may occur with minor stress or spontaneously. After the broken bone heals, the person may have chronic pain and a decreased ability to carry out normal activities. Osteoporosis may be due to lower-than-normal maximum bone mass and greater-than-normal bone loss. Bone loss increases after the menopause due to lower levels of estrogen, and after ' andropause' due to lower levels of testosterone. Osteoporosis may also occur due to a number of diseases or treatments, including alcoholism, anorexia, hyperthyroidism, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Density
Bone density, or bone mineral density, is the amount of bone mineral in bone tissue. The concept is of mass of mineral per volume of bone (relating to density in the physics sense), although clinically it is measured by proxy according to optical density per square centimetre of bone surface upon imaging. Bone density measurement is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk. It is measured by a procedure called densitometry, often performed in the radiology or nuclear medicine departments of hospitals or clinics. The measurement is painless and non-invasive and involves low radiation exposure. Measurements are most commonly made over the lumbar spine and over the upper part of the hip. The forearm may be scanned if the hip and lumbar spine are not accessible. There is a statistical association between poor bone density and higher probability of fracture. Fractures of the legs and pelvis due to falls are a significant public health pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart
The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to the lungs. In humans, the heart is approximately the size of a closed fist and is located between the lungs, in the middle compartment of the chest. In humans, other mammals, and birds, the heart is divided into four chambers: upper left and right atria and lower left and right ventricles. Commonly the right atrium and ventricle are referred together as the right heart and their left counterparts as the left heart. Fish, in contrast, have two chambers, an atrium and a ventricle, while most reptiles have three chambers. In a healthy heart blood flows one way through the heart due to heart valves, which prevent backflow. The heart is enclosed in a protective sac, the pericardium, which also contains a small amount of fluid. The wall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
