SUMMARY / RELATED TOPICS

Anatomy

Anatomy is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science which deals with the structural organization of living things, it is an old science. Anatomy is inherently tied to developmental biology, comparative anatomy, evolutionary biology, phylogeny, as these are the processes by which anatomy is generated over immediate and long timescales. Anatomy and physiology, which study the structure and function of organisms and their parts, make a natural pair of related disciplines, they are studied together. Human anatomy is one of the essential basic sciences; the discipline of anatomy is divided into microscopic anatomy. Macroscopic anatomy, or gross anatomy, is the examination of an animal's body parts using unaided eyesight. Gross anatomy includes the branch of superficial anatomy. Microscopic anatomy involves the use of optical instruments in the study of the tissues of various structures, known as histology, in the study of cells.

The history of anatomy is characterized by a progressive understanding of the functions of the organs and structures of the human body. Methods have improved advancing from the examination of animals by dissection of carcasses and cadavers to 20th century medical imaging techniques including X-ray and magnetic resonance imaging. Derived from the Greek ἀνατομή anatomē "dissection", anatomy is the scientific study of the structure of organisms including their systems and tissues, it includes the appearance and position of the various parts, the materials from which they are composed, their locations and their relationships with other parts. Anatomy is quite distinct from physiology and biochemistry, which deal with the functions of those parts and the chemical processes involved. For example, an anatomist is concerned with the shape, position, blood supply and innervation of an organ such as the liver; the discipline of anatomy can be subdivided into a number of branches including gross or macroscopic anatomy and microscopic anatomy.

Gross anatomy is the study of structures large enough to be seen with the naked eye, includes superficial anatomy or surface anatomy, the study by sight of the external body features. Microscopic anatomy is the study of structures on a microscopic scale, along with histology, embryology. Anatomy can be studied using both invasive and non-invasive methods with the goal of obtaining information about the structure and organization of organs and systems. Methods used include dissection, in which a body is opened and its organs studied, endoscopy, in which a video camera-equipped instrument is inserted through a small incision in the body wall and used to explore the internal organs and other structures. Angiography using X-rays or magnetic resonance angiography are methods to visualize blood vessels; the term "anatomy" is taken to refer to human anatomy. However the same structures and tissues are found throughout the rest of the animal kingdom and the term includes the anatomy of other animals.

The term zootomy is sometimes used to refer to non-human animals. The structure and tissues of plants are of a dissimilar nature and they are studied in plant anatomy; the kingdom Animalia contains multicellular organisms that are motile. Most animals have bodies differentiated into separate tissues and these animals are known as eumetazoans, they have an internal digestive chamber, with two openings. Metazoans do not include the sponges. Unlike plant cells, animal cells have neither chloroplasts. Vacuoles, when present, are much smaller than those in the plant cell; the body tissues are composed of numerous types of cell, including those found in muscles and skin. Each has a cell membrane formed of phospholipids, cytoplasm and a nucleus. All of the different cells of an animal are derived from the embryonic germ layers; those simpler invertebrates which are formed from two germ layers of ectoderm and endoderm are called diploblastic and the more developed animals whose structures and organs are formed from three germ layers are called triploblastic.

All of a triploblastic animal's tissues and organs are derived from the three germ layers of the embryo, the ectoderm and endoderm. Animal tissues can be grouped into four basic types: connective, epithelial and nervous tissue. Connective tissues are fibrous and made up of cells scattered among inorganic material called the extracellular matrix. Connective tissue holds them in place; the main types are loose connective tissue, adipose tissue, fibrous connective tissue and bone. The extracellular matrix contains proteins, the chief and most abundant of, collagen. Collagen plays a major part in maintaining tissues; the matrix can be modified to form a skeleton to protect the body. An exoskeleton is a thickened, rigid cuticle, stiffened by mineralization, as in crustaceans or by the cross-linkin

Maryland Route 547

Maryland Route 547 is a state highway in the U. S. state of Maryland. The highway runs 1.80 miles from MD 355 in North Bethesda east to MD 185 in Kensington. MD 547 connects North Kensington with Garrett Park in central Montgomery County; the highway was constructed in the early 1930s. MD 547 begins as an intersection with MD 355 opposite the entrance to Georgetown Preparatory School in North Bethesda; the state highway heads east as Strathmore Avenue, a two-lane road that passes the grounds of Strathmore, which features a namesake mansion and music center, to the south. After passing the Academy of the Holy Cross, MD 547 enters the town of Garrett Park; the highway passes through the Garrett Park Historic District several blocks to the south of the Garrett Park station on MARC's Brunswick Line. After serving as the town's main street, MD 547 veers southeast and its name changes to Knowles Avenue; the route enters Rock Creek Park, where the highway traverses intersects Beach Drive. At its junction with Summit Avenue, MD 547 enters the town of Kensington, where it reaches its eastern terminus at MD 185.

Knowles Avenue continues east for a block before ending at Armory Avenue in the Kensington Historic District. Garrett Park Road was resurfaced with macadam and widened with concrete shoulders from U. S. Route 240 east to the Kensington town limit at Summit Avenue between 1931 and 1933. MD 547's bridge across Rock Creek was completed in 1932. In 1936, the state highway was extended east two blocks to the new alignment of MD 193; that highway's present course through Kensington was completed as part of a railroad grade separation project that same year. MD 547 has had only minor changes since the 1930s; the entire route is in Montgomery County. Maryland Roads portal MDRoads: MD 547

Bluehead chub

The bluehead chub ) is a cyprinid native to North America. Its name is due to its appearance. Adult bluehead chubs are, on average, between 160 mm in length, they have a robust body with uniformly large scales. The scales are present on the breast, they have a pored body, a weakly falcate pectoral fin, pharyngeal teeth. They have a large mouth, small eyes, a terminal barbel. Other characteristics include a darkened lateral band, spot on the caudal fin, red coloration of the fins and iris of the eyes, they have 8 anal rays. The bluehead chub is a freshwater fish, lives in pools and streams, they feed on plants. Bluehead chubs inhabit freshwater pools and small to medium rivers with sandy or rocky bottoms, they live in warm to cool waters that have swift currents and are turbid. Bluehead chubs spawn in the spring and reproduce by external fertilization in which the female releases eggs onto the bottom and the male releases sperm to fertilize the eggs; the male makes a nest of gravel in a mound for the female to deposit the eggs.

After fertilization, the male guards the eggs. They mature for three years before reaching reproductive maturity; the bluehead chub can be found in the southeastern United States. It is distributed throughout the York River system of Virginia, the Atlantic and Gulf coast drainage, the lower Mississippi River drainage into Mississippi and Louisiana, its range includes Virginia, West Virginia, Mississippi, North Carolina and Louisiana. As a result of bait bucket releases by fishermen, the bluehead chub has spread to multiple drainage basins in which it is not native; the genus name Nocomis comes from the Native American name for "grandmother"