Introduction & Brief History of Transmission Electron Microscopy
Transmission electron microscopy is applied to many different fields from biological sciences to industrial settings. TEM technology works on a theory first proposed by Louis de Broglie in the 1920s, that electrons have wave like characteristics that are lower than that of visble light. Luis de Broglie’s theory was confirmed in the 1930s by physicts Clinton Davisson and Lester Germer with an electron-diffraction experiment that proved that electrons had wave properties. The first image was produced by Knoll and Ruska in 1932 utilizing electrons. Further innovation on TEM has led to proven techniques that produce images that can be magnified up to 50 million times. TEM works by utilizing electrons that pass through ultrathin sections of samples. As the electrons pass through the sample an image is formed and projected out. Because of the magnification ability, TEM has become an invaluable tool in the biological science especially is ultrastructural anatomy of cells. Transmitting electron microscopy has allowed better understanding of cellular composition and better taxonomic classification of organisms. The aim of this is to describe how Transmitting Electron Microscopy has been utilized in researching dinoflagellates and to propose future implications of using TEM to further knowledge about dinoflagellates.
Dinoflagellates General Characteristics
Basic generalizations of Dinoflagellates are that they are found in fresh and marine waters that and date back to millions of years. dinoflagellates are a diverse group of eukaryotes that can range from nonmotile to swimming organisms. But in spite of the diversity exhibited throughout the group there are some chara...
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...s in humans if ingested. P. lunlua is an unarmored biolumnesis species of dinoflagellates that utilizes its bioluminescent for protection by illuminating its predators so other predators can see. P. sociale is a motile species that has a very thick thecal plates and little research has been done with this species of Peredniuim. The ideal outcome of this research is to find novel differences in the ultrastructural characteristics of K. brevis, P. lulnula and P.sociale and to provide a better description of each species.
TEM an priceless tool in the biological science. Without TEM the detailed information on dinoflagellates would be incomplete. Although dinoflagellates are still hard to place in taxonomic trees, TEM has allowed better characterization of dinoflagellates helped better understand the morphological differences between species of dinoflagellates.
Sabellaria cementarium belongs to the phylum Annelids and is an invertebrate polychaete species. They are found in small clumps at the rocky bottoms of the sea floor where they use the rich source of natural phytoplankton as their primary diet (Qian and Chia, 1990). The tube-like worms can behave social and form extensive reefs or independently build hollow tubes in to the sandstone (pawlik and Chia, 1991). Embryos form a polar lobe that is absorbed in to the blastomeres at the end of division. Larval development and movement follows shortly after the 14-15 hour fertilization period where spiral cleaving of the fertilized oocytes appears (Render, 1983). Much is still not known about the invertebrate worm in their natural niche.
Brachiopod: One organism that is a part of the Lophophore is the brachiopod. Brachiopods are marine animals that look like claims. Actually they are quite different from claims in their anatomy, related to the bryozoan and phoronida.Brachiopods is very rare in the seas. They often make their homes in very cold water, either in Polar Regions or at great depths in the ocean, and are not often encountered. There are about 300 living species of brachiopods.250 million years ago; they were in the wo...
Many different squid exist, and along with different species comes different looks, however, all squid are based on a basic body plan. The average squid species range from as tiny as 2 cm to as threatening as two metres in length. However, Teuthids range from the Antarctic up-to-14-metres Colossal Squid (Mesonychoteuthis hamiltoni) to the tiny less-than-one-inch Grass Squid (Pickfordiateuthis pulchella). The elongated body, also called the mantle, is slightly swollen near the middle and tapers to a blunt point. At this point is the head, at which point the tentacles begin. Also at the head is the mouth of the squid, which has a sharp, bird-like beak used like teeth. All species of squid possess long, cylindrical bodies and an internal, blade-shaped gladius. A gladius is made of chitin, like human fingernails, and lends s...
Soft corals such as sea fingers and sea whips, are soft and bendable and often resemble plants or trees. These corals do not have stony skeletons, but instead grow wood-like cores for suppor...
Cyanobacteria are one of the largest and most important groups of bacteria on the earth. Often called ‘the blue-green algae’ Cyanobacteria is in fact, not an algae at all. Algae are eukaryotic, whereas cyanobacteria, is a bacteria, and is prokaryotic. The name algae is used to refer to any aquatic organisms capable of photosynthesis, so the term is considered general, though in this case, inaccurate. Being tiny and normally unicellular, cyanobacteria grow in large colonies, making them visible to the human eye, and often dominate aquatic habitats such as shorelines. Over their 3.5 billion year reign, Cyanobacteria have helped to successfully establish the earth’s atmosphere, making it possible for human life forms to thrive and some of the oldest known fossils in the world are cyanobacteria, earning it the title of one of the great survivors of all time.
On every continent we find fossils of sea creatures in rock layers that today are high above sea level. For example, most of the rock layers in the walls of the Grand Canyon contain marine fossils. This includes the Kaibab Limestone at the top of the strata sequence and exposed at the rim of the canyon, which today is 7,000–8,000 feet above sea level.2 This limestone was therefore deposited beneath lime sediment-charged ocean waters, which swept over northern Arizona (and beyond). Other rock layers of the Grand Canyon also contain large numbers of marine fossils. The best example is the Redwall Limestone, which commonly contains fossil brachiopods (a type of clam), corals, bryozoans (lace corals), crinoids (sea-lilies), bivalves (other types
The use of meiofauna as a biological indicator is a more recent development than the utilization of macrofauna in the assessment and monitoring of aquatic ecosystem (Coull & Chandler, 1992). Meiofauna is thought to be jointly connected to the other faunal compartments as they are the most richest benthic group. Foraminifera and Nematode are two major protozoans usually found in the sand sediment.
The outer layer of a reef consists of living animals, or polyps, of coral. Single-celled algae called zooxanthellae live within the coral polyps, and a skeleton containing filamentous green algae surrounds them. The photosynthetic zooxanthellae and green algae transfer food energy directly to the coral polyps, while acquiring scarce nutrients from the coral. The numerous micro habitats of coral reefs and the high biological productivity support a great diversity of other life.
Coral reefs are the most biodiverse ecosystem on the planet. There are more than 25,000 known species of organisms and countless others that have yet to be identified (Helvarg, 2000). Reefs thrive on the shallow edge of tropical seas, most often on the eastern edge of continents along warm water currents that brush the coasts. Reefs cannot live in cold waters and are limited by ocean depth and available sunlight. Coral is the foundation of the reef community, providing a three-dimensional structure where thousands of species of vertebrates and invertebrates live and feed. Some species of coral are hard, while others soft. Some are branched, yet others are compact and rounded. Coral is made up of large communities of tiny jellyfish like polyps. These polyps absorb calcium from the sea water and secrete a hard limestone skeleton. At night the polyps extend sticky, stinging tentacles from their skeletons to capture and consume small floating organisms such as zooplankton. Every coral has a two-stage life cycle: the larva, and the polyp. The larval stage is free swimming, and the polyp is stationary. Ocean currents carry the larva from the stationary parent polyp to any hard, clean, silt-free surface where, if the conditions are perfect, the larva grows into a coral forming polyp, never to move again (Levin, 1999). One of the most valuable resources for coral polyps are algae. Some live on the coral skeletons, but one type in particular, zooxanthellae, lives inside the tissue of the polyps. Zooxanthellae makes up about half the weight of the fleshy polyps and are not only a valuable food resource, but they are responsible for the brilliant colors associated with coral. When coral looses these prec...
The Burgess Shale Fauna is a fauna that was constructed based on a group of fossils that were initially found, in the Burgess Shale area in the Canadian Rockies (Gould, 1989). They are a very important group of fossils as “modern multicellular animals make their first unprotected appearance in the fossil record some 570 million years ago” through this group (Gould, 1989, pp. 24). Moreover the Burgess Shales are known to have preserved the soft parts of animals enabling us to get a better understanding of life at the time.
These particular invertebrates have been found to physically manipulate their environment by prey manipulation, burying and den excavation, arm dexterity, den barricading with rocks/coral. The observations of such behaviors have led scientist to believe cephalopods have the capacity to employ tools (Finn, 2009). Cephalopoda is also known for their body-patterning abilities for interspecific and intraspecific communication. The cephalopod skin has been deemed a very complex and sophisticated organ in itself. Cephalopoda skin colors and textures are regulated by intricate neuromuscular mechanisms. Chromatophores are the reason behind their skin appearance. Chromatophores are large pigment-containing cells distributed in the superficial layers of the skin over the whole surface of the body. By equal and unequal dilation of chromatophores, a variety of patterns and colors are produced causing the animal to become darker, lighter (Barbato, 2007). The Cephalopoda’s sophisticated development, their ability to learn, and the how they can physically manipulate their environment pronounces them the most intelligent
Soft corals are grouped in the phylum Cnidaria, class Anthozoa, and order Alcyonacea. Their distinguishing characteristic is that their polyps always bear eight tentacles which are on both edges fringed by rows of pinnules (Fabricius and De’ath, 2002). The common name “soft coral” comes from the fact that they have no massive external skeleton as compared to the more commonly studied hard corals.
Coral reefs are the most biologically diverse marine ecosystems. Driving this diversity are cnidarian corals which are obligate mutualistic symbioses between coral animals and dinoflagellate algae of the genus symbiodinium. These algae are commonly called zooxanthellae. This symbiosis between heterotrophic hosts and photosynthetic symbionts allows coral to thrive in nutrient poor seas and deposit calcium carbonate to build reefs (Toller et al. 2001, 348).
The giant pacific octopus is in the kingdom Animalia because it is multicellular, eukaryotic, and has no cell walls. In addition to this, the giant pacific octopus reproduces sexually and has cells that are used for specific functions. (Kalupa, 2012)
Directing your attention toward the taxonomy of sea dragons you will notice that our of five kingdoms, Animalia or Metazoa kingdom suits this perticuar organism the best as it is multicellular and eukaryoticheterotroph(bodies do not make its own food), have skeletal support system of some sort, and reproduce sexually(Myers),. Next, the phylum of sea dragons is Chordata. Chordata is the phylum that includes all the animals that have a notochord, or nerve cord, at some stage of their development (Kennedy). The class of this animal is Actinopterygii. After that is their order which is Syngnathiformes. Also sea dragons belong to the family syngnathidae which derived from Greek meaning "fused jaw", a trait that all members of this family have in common(Sara A). As a member of the syngnathidae family, which are mostly marine fish and comprise of about 200 species of pipefishes in 54 genera, including the weedy sea dragon (Phyllopteryx taeniolatus) and the leafy sea dragon (Phycodurus eques)(eol). Now we have stated toaxomic classification it’s time to get acclima...