The protozoan commonly known as the “water bear” is an extremophile that has engaged many in the scientific community. The Tardigrade is an invertebrate that has eight legs and comes in many shapes and sizes. This group has many adaptations such as cryptobiosis that allows it to survive in extreme environments. The Tardigrade can be found from land, to water, to sulfur springs, and to over 25 species found in the frozen tundra of Antarctica (Miller et al, 2001). To understand these creatures this paper will summarize the taxonomy, reproduction, food, and protective genetics, of the Tardigrades. The first section to this paper will examine is how these creatures are divided taxonomically.
The “water bear” is a common name for a group of a little over 100 genera of protozoans grouped under the Phylum Tardigrada and is a relative of the Phylum Arthropoda. The phylum Tardigrada contains over 1000 species, and is grouped into three classes. There are two main classes the Heterotarigrada ad the Eutardigrada. The last is the Mesotardigrada and contains only one species, that was discovered in a sulfur spring in Japan 1937, and has not been seen since. “Water bears” are, as with most species, separated into groups by characteristics and more recently molecular genetic methods. The Heterotarigrada are known mainly for their hair like tufts on appendages and hard-undivided flattened scales. The Eutardigrada are known as “naked tardigrades” because they lack the hard scales or have several separate plates. Tardigrades are then divide further into orders by comparing groups for cuticle appearance, feeding tube, claws, and other defining features (Michalczyk, 2014).
The tardigrade, due to the possibility of its habitat constantly changing,...
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...is first made through a biochemical pathway of using lipids and glyoxylating them. The trehalose allows the cells to be reduced to less than two percent water content. Trehalose is found in lower plants and protozoans and is comparable to sucrose in higher organisms. The most recent evidence shows that trehalose molecules interact with macromolecules and membranes of the cell and stabilize them during low water periods. Experiments have shown that cells membranes dried with trehalose once rehydrated resume normal functions. This is contrary to those without trehalose where biological functionality is lost. It is also believed that trehalose could be use in place of bulk water. These protective qualities allow for tardigrades to be revived many years after desiccation. In one case tardigrades were revived from a moss sample that was over 120 years old. (Crowe, 2014)
Hyla versicolor, commonly know as the Gray Tree Frog or the Eastern Gray Tree Frog, is an amphibian that is referred to as the “Chameleon of the Frog world” (Craighead, 2004, p.1) because of its ability to change colors. “This frog was once thought to be the same species as the Cope’s Gray Tree Frog”. They can only be distinguished by their calls and the fact that the Cope Gray Tree Frog is diploid while the Gray Tree Frog is tetraploid (NPWRC, 2004). The Gray Tree Frog is classified as follows:
ohn Steinbeck's “Cannery Row” offers many interpretations, especially when viewed through the lens of the Holy Bible. From the Christ like figure of Doc to his apostles, Mack and the boys, Cannery Row is ripe with religious tropes. However, Doc is also considered to be quick to anger at times, and carries with him many themes found throughout the Old Testament texts and some legends that are even more aged. However, if we consider Doc to be the messianic figure he is then it wasn't the party that Doc had a problem with, nor that it was held without his knowing on his property. The issue arises with the process by which Mack and the boys use to fund the party. The green frogs harvested ultimately causes Mack and the boys to succumb to greed in an effort to praise Doc. The collection of frogs used as a currency is what sends Doc into a rage.
Audesirk, Teresa, Gerald Audesirk, and Bruce E. Byers. Biology: Life on Earth with Physiology. Upper Saddle River, NJ: Pearson Education, 2011. 268-69. Print.
Like almost any other animal the octopus has many dangers that they need to hide from. Octopuses are masters of camouflage and have amazing defensive skills that can be used for fighting. Octopi are known for defending themselves against small sharks and other dangerous predators. An octopus uses its color changing abilities to blend in with its surroundings and to warn other animals to prevent them from attacking the octopus.
.... (2011). A New Arthropod Jugatacaris agilis n. gen. n. sp. from the Early Cambrian Chengjiang Biota, South China. Journal of Paleonotology, 85(3), 567-586. doi:10.1666/09-173.1
The Biological Importance of Water as a Solvent and as a Medium for Living Organisms
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.
With its abundance of genera, the Burgess Shale is one of the world’s most important fossil fields. It’s discovery in 1909 led to over 100 years of paleontological study in the Canadian Rockies, a majority of which has been carried out in two quarries known as the Walcott and Raymond quarries (Hagadorn, 2002). Though he was originally in search of trilobites in the Burgess Shale Formation, paleontologist Charles Walcott also discovered a diverse group of soft- and hard-bodied fossils, from algae and sponges to chordates and cirripeds (Hagadorn, 2002). Soft-bodied fossils are incredibly rare due to their delicate structure and susceptibility to decay, so it is hard-bodied fossils that more regularly occur in fossil findings. However over 75,000 soft-bodied specimens have been found in the Burgess Shale formation (Hagadorn, 2002). These specimens are preserved in layers of shale formed from deposits of fine mud. One of the most significant species discovered is the Pikaia gracilens. Believed to be an early chordate, the Pikaia gracilens existed very close to the beginning of the evolutionary path that ultimately lead to humans (McGraw-Hill Encyclopedia, 2006).
Diplopoda is a class, belonging to the subphylum of Arthropoda Myriapoda, consisting of about 10 000 species of animals which have two pairs of legs for each body segment and are often known as Millipedes. Hence the name, they do not have one thousand legs.
Frogs are amphibians in the order Anura. The order Anura is broken down into 22 different families of frogs and toads. Although they belong to the same order, frogs and toads are different in a lot of ways. Some of the more distinct differences are their skin and where they live. Frogs usually have smooth moist skin and toads usually have dry watery looking skin. Frogs spend most of their lives in or near water and toads spend more time on land. Amphibian means "double life." Frogs and toads each have two parts to their lives: when they live on water and when they live land. A frog's life starts in the water when it is hatched from an egg as a tadpole. A tadpole looks very different from an adult frog. A tadpole has a tail, no limbs, and breathes through gills. After a while the tadpole goes through metamorphosis. During the change the frog grows limbs, the tail disappears, it uses lungs to breathe, and it doesn't have to live in water anymore. As a tadpole, the frog feeds mostly on vegetation. The tadpoles have a small rasping mouth suited especially for scraping algea from the bottom of ponds. Depending on the species, it can take a few weeks to a year or more for the tadpoles to become fully grown. Not all frogs hatch as tadpoles. Some species of frogs hatch as froglets. Froglets look just like adult frogs but are a lot smaller. Froglets don't go through a metamophosis. Most species that hatch as froglets are found in dry places. Frogs who live in dry places where rains are seasonal have to grow up quickly because a tadpole will die if their temporary pond dries up. Adult frogs can live in water or on land, but it always needs to be near water so its respiratory organs don't dry out.
Osmosis is a biological process. If equilibrium is ever achieved, then water molecules will move. back and forth between the substances. If a surrounding sucrose solution has a lower water potential than the plant tissue in the solution, then, through osmosis water will move from the tissue into the. the surrounding solution, the tissue will lose mass and length as a result.
Frogs are needed for everyday life. They are part of pond life. Each animal is important because even in the pond, there is a food chain. Frogs are amphibians, animals that spend half of their lives under water, and remainder on land. The first frog appeared in the early Jurassic period about 200 million years ago.
middle of paper ... ... World Book Inc, 2000. Davis, Lloyd S. and John T Darby. Penguin Biology. San Diego: Academic Press, Inc., 1990.
As many know, there are places on this earth where conditions are too inhospitable for humans to live. There are places with skull crushing depths, boiling water and high methane concentrations, where no human could survive. Survival in such hostile conditions was thought to be impossible for any organism; until the late 1960’s when bacterial microorganisms were found living in scalding thermal environments above 70 degrees Celsius, in Yellowstone National Park (Madigan & Marrs, 1997). These microorganisms were later termed extremophiles for their “love” of environments that are too hostile for other organisms to tolerate. Therefore, the capabilities and differences among extremophiles deserves a thorough investigation compared to the most adaptable species on the planet, humans.