The Appalachian Mountains, often called the Appalachians, are a system of mountains in eastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They once reached elevations similar to those of the Alps and the Rocky Mountains before experiencing natural erosion. The Appalachian chain is a barrier to east–west travel, as it forms a series of alternating ridgelines and valleys oriented in opposition to most highways and railroads running east–west.
Topoisomerases are enzymes that participate in the overwinding or underwinding of DNA. The winding problem of DNA arises due to the intertwined nature of its double-helical structure. During DNA replication and transcription, DNA becomes overwound ahead of a replication fork. If left unabated, this torsion would eventually stop the ability of DNA or RNA polymerases involved in these processes to continue down the DNA strand.
The Mule Mountains are a north/south running mountain range located in the south-central area of Cochise County, Arizona. The highest peak, Mount Ballard, rises to 7,500 ft (2,300 m). Prior to mining operations commencing there, the mountains were heavily forested with large Rocky Mountain Douglas-fir and other conifers, but these were all cut down for housing needs and to feed the ore smelting furnaces in Douglas, Arizona, approximately 20 miles due east. Now, the primary vegetation of the Mules consists of manzanita brush, juniper, lowland oaks and pines, and various grasses. To the east of the mountain range lies Sulphur Springs Valley, and the San Pedro River and Valley to the west.
Muricidae is a large and varied taxonomic family of small to large predatory sea snails, marine gastropod mollusks, commonly known as murex snails or rock snails. With about 1,600 living species, the Muricidae represent almost 10% of the Neogastropoda. Additionally, 1,200 fossil species have been recognized. Numerous subfamilies are recognized, although experts disagree about the subfamily divisions and the definitions of the genera. Many muricids have unusual shells which are considered attractive by shell collectors and by interior designers.
The Shawangunk Ridge, also known as the Shawangunk Mountains or The Gunks, is a ridge of bedrock in Ulster County, Sullivan County and Orange County in the state of New York, extending from the northernmost point of New Jersey to the Catskill Mountains. Shawangunk Ridge is the continuation of the long, easternmost ridge of the Appalachian Mountains; the ridge is known as Kittatinny Mountain in New Jersey, and as Blue Mountain as it continues through Pennsylvania. This ridge constitutes the western border of the Great Appalachian Valley.
The Cahaba River is the longest substantially free-flowing river in Alabama and is among the most scenic and biologically diverse rivers in the United States. It is a major tributary of the Alabama River and part of the larger Mobile River basin. With headwaters near Birmingham, the Cahaba flows southwest, then at Heiberger turns southeast and joins the Alabama River at the ghost town and former Alabama capital of Cahaba in Dallas County. Entirely within central Alabama, the Cahaba River is 194 miles (312 km) long and drains an area of 1,870 square miles (4,800 km2).
Mirey Brook is a 6.5-mile-long (10.5 km) stream in northern Massachusetts and southwestern New Hampshire in the United States. It is a tributary of the Ashuelot River, itself a tributary of the Connecticut River, which flows to Long Island Sound.
The gastropod shell is part of the body of a gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or the shell is reduced such that the body cannot be retracted within (semi-slug). Some snails also possess an operculum that seals the opening of the shell, known as the aperture, which provides further protection. The study of mollusc shells is known as conchology. The biological study of gastropods, and other molluscs in general, is malacology. Shell morphology terms vary by species group. An excellent source for terminology of the gastropod shell is "How to Know the Eastern Land Snails" by John B. Burch now freely available at the Hathi Trust Digital Library.
Discus is a genus of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Discidae, the disk snails.
The Cahaba pebblesnail, scientific name Clappia cahabensis, is a species of very small freshwater snail, aquatic gastropod mollusks in the family Lithoglyphidae.
For Clappia software, see Clappia.
Paravitrea is a genus of small, air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Zonitidae, the true glass snails.
Sonorella is a genus of land snails in the family Helminthoglyptidae. They are known commonly as talussnails or talus snails because most live in talus and similar habitat. They are distributed across the southwestern United States and adjacentMexico. There are about 80 species.
Succinea sanctaehelenae is a species of land snail in the family Succineidae, the amber snails. It is known commonly as the blushing snail. It is endemic to the island of Saint Helena in the South Atlantic Ocean.
Polygyridae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea.
Cryptomastix mullani is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Polygyridae.
Planogyra is a genus of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Valloniidae.
Cerodrillia clappi is a species of sea snail, a marine gastropod mollusk in the family Drilliidae.
Nescopeck Mountain is a ridge in Columbia County and Luzerne County, in Pennsylvania, in the United States. Its elevation is 1,594 feet (486 m) above sea level. The ridge is a forested ridge, with at least two types of forest and two systems of vernal pools. It is a very long and unbroken ridge with two water gaps: one carved by Catawissa Creek and one carved by Nescopeck Creek. This later gap was exploited as a transportation corridor with the construction of the Lehigh & Susquehanna Turnpike between the respective frontier communities at Lausanne Landing and Nescopeck in 1805 connecting the newly developing Wyoming Valley with Philadelphia and the Delaware River valley; cutting off over 100 miles between Philadelphia and Wilkes-Barre. Today's Route PA 93 derives from this historic pack mule road.
Sinforosa Eyang Nguema Nchama, also known as Mirey and Mirey de Fifi, is an Equatoguinean football manager and former player who coaches Deportivo Evinayong in the Equatoguinean women's league.
