The internal and external anatomy of Labeo umbratus
Hannah Janse van Vuuren
Abstract
The anatomy of an Labeo umbratus specimen, found in the Krugersdrif dam, was studied. Annotations of the positions of the internal organs as well as the external morphological characteristics were made. Upon further analysis, several characteristics were identified that would have eased life in aquatic environments. Some of these characteristics include, sensory receptors located on the head as well as on the lateral view of the body, the shape of the fish, specialised, paired appendages, respiratory structures as well as structures aiding the fish in buoyancy. The way in which the internal organs and the external appendages were arranged in and on the fish, showed great evolutionary adaptations to the water environments in which they reside.
Key words
adaptations, Labeo umbratus, morphology, specialised, water
Introduction
The main interest during the dissection of Labeo umbratus, was to identify the most important structures and adaptations present, that allowed the fish to lead a successful life in a
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Secondly, the elongated gonads are located beneath the swim bladder. This specimen was male because it only had one urogenital pore behind the anus and the bright orange tissue of the testis was found near the intestines. The digestive tract is then removed as a whole and consist of the esophagus, stomach, pyloric ceca, intestines and anus. The digestive organs are often covered with a fat layer of insulation purposes. The cream coloured liver and gallbladder are removed along with the digestive organs. These organs are then separated from the digestive tract by cutting the membranes that join them. The liver is the largest of all the internal organs and the gallbladder is green, because of the bile
Fox, R. 2001. Invertebrate Anatomy OnLine: Artemia Franciscana. Lander University. http://webs.lander.edu/rsfox/invertebrates/artemia.html, retrieved February 13, 2011.
The gallbladder according to Dorland’s Medical Dictionary is ‘the pear shaped reservoir for the bile on the posteroinferior surface of the liver, between the right and the left quadrate lobe, from its neck the cystic duct projects to join the common bile duct’. The function of the gallbladder in the human body is to solve and concentrate bile, which is produced by the liver and is necessary for proper digestion of fats.
Mink Intro – External Anatomy Overview. (n.d.). mreroh.com . Retrieved May 27, 2014, from http://www.mreroh.com/student/apdocs/Dissection/Intro%20-%20External%20Anatomy.pdf
Study done from the available fossils show that the body of Liopleurodon was very streamlined and adapted to swimming. Its body had four limbs which were paddle-like in shape. These paddle shaped limbs acted like propellers which made it
The background of this article gives information that is necessary to understand the experiment. The shape of the pelvic girdle is an appropriate predictor of both phylogeny and movement in terrestrial vertebrates. However, in marine vertebrates, the gravitational forces typically applied to terrestrial pelvic girdles are not there and therefore have little impact on the shape of the girdle. Pelvic girdles of fish are generally not attached to the vertebrae and primarily are used as a place for muscles to attach and supporting of the fins. The authors discuss how in many cases the pelvic girdle could be removed and not result in any complications. However, there are some marine vertebrates that are capable of bottom walking on the ocean floor with their fins. In batoids, the pelvic fins are used for walking, which is when pelvic fins move in an alternating fashion, or punting, when both pelvic fins move at the same time. There is also augmented punting; this is when the vertebrate uses both the pectoral fins and the pelvic fins to generate more thrust, this action decreases the forces on the pelvic fins during a punt. While this locomotion would
Although the Hippocampus spp. are placed into the same class as other organisms more traditionally viewed as fish, their morphology bears distinct differences in comparison to other bony fish. The various species belonging under the genus Hippocampus range in maximum size from 20 mm to 300 mm(Foster 8). Their physical appearance is distinct from other members of its class due to their "horse-like head, monkey-like tail, and kangaroo-like pouch."( Lourie et al 12) Morphologically, seahorses do not have scales like traditional fish, but rather posses bony plates covered by skin. The appearance of bony extrusions and skin ...
The digestive system of the horse consists of a simple stomach, small intestines, cecum, large and small colons, rectum and anus. The horse’s stomach is comparatively small for its size. The stomach of an average horse has a holding capacity of about two gallons. This may be the reason horses eat small but frequent meals. From the stomach food moves to the small intestine, which is the main site of digestion. The small intestine empties into the cecum. The cecum; along with the large colon; make up the large intestine. Digestion in the large intestine occurs by action of bacteria and protozoa. (arg.gov.sk.ca)
The pancreas is located in the middle of the abdomen. It’s surrounded by the stomach, small intestine, liver and spleen. It’s about six inches long and shaped like a thin pear, wide at one end. It has three sections: wider right end is the head, the middle is the body and the left end is the tail.
The Axolotl, a crucially endangered neotenous species of mole salamander, has adapted to fit its environment so it can easily catch food and evade predators. The Axolotl’s habitat is the lake system of Xochimilco that is near Mexico City, Mexico. This shallow, fresh water lake complex has a temperature range of 6- 20°C and a pH of 7- 12. The complex also has the Axolotl’s primary food sources of mollusk, insect larvae, and other crustaceans. However, with the introduction of foreign species such as the Asian Carp and the African Tilapia, the Axolotl now has predators that may eat and threaten it, and it has competition for the animals it usually eats. Fortunately, the Axolotl has developed adaptations that aid it in catching food and evading predators. To help it catch food the Axolotl’s teeth are shaped like cones, so that its “vacuum” action of sucking in as much water in order to also eat food is aided by the shape of the teeth, which allow it to grip, rather than chew. To aid them in avoiding predators they are able to metamorphose so that they use their lungs more than their gill, which allows them to leave very toxic waters and the predators within. Another adaption that helps them deflect any predator is that they are able to regenerate body parts that have been lost, allowing them to stay as strong as possible. Axolotl’s have adaptations that aid their survival from predators in the lake complex Xochimilco that they reside in.
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