|
Comparative Foot Morphology
Comparative foot morphology involves comparing the form of distal limb structures of a variety of terrestrial vertebrates. Understanding the role that the foot plays for each type of organism must take account of the differences in body type, foot shape, arrangement of structures, loading conditions and other variables. However, similarities also exist among the feet of many different terrestrial vertebrates. The paw of the dog, the hoof of the horse, the ''manus'' (forefoot) and ''pes'' (hindfoot) of the elephant, and the foot of the human all share some common features of structure, organization and function. Their foot structures function as the load-transmission platform which is essential to balance, standing and types of locomotion (such as walking, trotting, galloping and running). The discipline of biomimetics applies the information gained by comparing the foot morphology of a variety of terrestrial vertebrates to human-engineering problems. For instance, it may prov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comparative View Of The Human And Elephant Frame, Benjamin Waterhouse Hawkins, 1860
general linguistics, the comparative is a syntactic construction that serves to express a comparison between two (or more) entities or groups of entities in quality or degree - see also comparison (grammar) for an overview of comparison, as well as positive and superlative degrees of comparison. The syntax of comparative constructions is poorly understood due to the complexity of the data. In particular, the comparative frequently occurs with independent mechanisms of syntax such as coordination and forms of ellipsis (gapping, pseudogapping, null complement anaphora, stripping, verb phrase ellipsis). The interaction of the various mechanisms complicates the analysis. Absolute and null forms A number of fixed expressions use a comparative form where no comparison is being asserted, such as ''higher education'' or ''younger generation''. These comparatives can be called ''absolute''. Similarly, a null comparative is one in which the starting point for comparison is not stated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Experimental Zoology
''Journal of Experimental Zoology'' is a peer-reviewed scientific journal of zoology established in 1904. In 2003, the journal was split into the ''Journal of Experimental Zoology Part A: Ecological Genetics and Physiology,'' currently edited by David Crews and Randy Nelson and the ''Journal of Experimental Zoology Part B: Molecular and Developmental Evolution'', currently edited by Ehab Abouheif. Both parts are currently published by Wiley-Blackwell Wiley-Blackwell is an international scientific, technical, medical, and scholarly publishing business of John Wiley & Sons. It was formed by the merger of John Wiley & Sons Global Scientific, Technical, and Medical business with Blackwell Publish .... Originally, part A was called Comparative Experimental Biology until 2007 when it changed to Ecological Genetics and Physiology, but it is now titled Ecological and Integrative Physiology. Part B has kept the name it took during the split, Molecular and Developmental Evolution. Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tendon
A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability to withstand significant amounts of tension. Tendons are similar to ligaments; both are made of collagen. Ligaments connect one bone to another, while tendons connect muscle to bone. Structure Histologically, tendons consist of dense regular connective tissue. The main cellular component of tendons are specialized fibroblasts called tendon cells (tenocytes). Tenocytes synthesize the extracellular matrix of tendons, abundant in densely packed collagen fibers. The collagen fibers are parallel to each other and organized into tendon fascicles. Individual fascicles are bound by the endotendineum, which is a delicate loose connective tissue containing thin collagen fibrils and elastic fibres. Groups of fascicles are bounded by the epitenon, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metatarsal
The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the medial side (the side of the great toe): the first, second, third, fourth, and fifth metatarsal (often depicted with Roman numerals). The metatarsals are analogous to the metacarpal bones of the hand. The lengths of the metatarsal bones in humans are, in descending order, second, third, fourth, fifth, and first. Structure The five metatarsals are dorsal convex long bones consisting of a shaft or body, a base (proximally), and a head (distally).Platzer 2004, p. 220 The body is prismoid in form, tapers gradually from the tarsal to the phalangeal extremity, and is curved longitudinally, so as to be concave below, slightly convex above. The base or posterior extremity is wedge-shaped, articulating proximally with the tarsal bones, and by it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digitigrade
In terrestrial vertebrates, digitigrade () locomotion is walking or running on the toes (from the Latin ''digitus'', 'finger', and ''gradior'', 'walk'). A digitigrade animal is one that stands or walks with its toes (metatarsals) touching the ground, and the rest of its foot lifted. Digitigrades include walking birds (what many assume to be bird knees are actually ankles), cats, dogs, and many other mammals, but not plantigrades or unguligrades. Digitigrades generally move more quickly and quietly than other animals. There are anatomical differences between the limbs of plantigrades, like humans, and both unguligrade and digitigrade limbs. Digitigrade and unguligrade animals have relatively long carpals and tarsals, and the bones which would correspond to the human ankle are thus set much higher in the limb than in a human. In a digitigrade animal, this effectively lengthens the foot, so much so that what are often thought of as a digitigrade animal's "hands" and "feet" correspon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cartilage
Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck and the bronchial tubes, and the intervertebral discs. In other taxa, such as chondrichthyans, but also in cyclostomes, it may constitute a much greater proportion of the skeleton. It is not as hard and rigid as bone, but it is much stiffer and much less flexible than muscle. The matrix of cartilage is made up of glycosaminoglycans, proteoglycans, collagen fibers and, sometimes, elastin. Because of its rigidity, cartilage often serves the purpose of holding tubes open in the body. Examples include the rings of the trachea, such as the cricoid cartilage and carina. Cartilage is composed of specialized cells called chondrocytes that produce a large amount of collagenous extracellular matrix, abundant ground substance that is rich in pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiber
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, for example carbon fiber and ultra-high-molecular-weight polyethylene. Synthetic fibers can often be produced very cheaply and in large amounts compared to natural fibers, but for clothing natural fibers can give some benefits, such as comfort, over their synthetic counterparts. Natural fibers Natural fibers develop or occur in the fiber shape, and include those produced by plants, animals, and geological processes. They can be classified according to their origin: *Vegetable fibers are generally based on arrangements of cellulose, often with lignin: examples include cotton, hemp, jute, flax, abaca, piña, ramie, sisal, bagasse, and banana. Plant fibers are employed in the manufacture of paper and textile (cloth), and die ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horse Hoof
A horse hoof is the lower extremity of each leg of a horse, the part that makes contact with the ground and carries the weight of the animal. It is both hard and flexible. It is a complex structure surrounding the distal phalanx of the 3rd digit (digit III of the basic pentadactyl limb of vertebrates, evolved into a single weight-bearing digit in horses) of each of the four limbs, which is covered by soft tissue and keratinised (cornified) matter. Anatomy The hoof is made up of two parts. The outer part, called the hoof capsule, is composed of various cornified specialized structures. The inner, living part of the hoof, is made up of soft tissues and bone. The cornified material of the hoof capsule differ in structure and properties. Dorsally, it covers, protects, and supports P3 (also known as the coffin bone, pedal bone, or PIII). Palmarly/plantarly, it covers and protects specialised soft tissues, such as tendons, ligaments, fibro-fatty and/or fibrocartilaginous tissues, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscosity
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's axis than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the strength of the compensating force is proportional to the fluid's viscosity. In general, viscosity depends on a fluid's state, such as its temperature, pressure, and rate of deformation. However, the dependence on some of these properties is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
