Platyhelminthes are mainly known as flatworms. These flatworms are bilaterally symmetrical and are triploblastic. Platyhelminthes are also acoelomates and participate in gaseous exchange through diffusion in the tegument layer. Platyhelminthes are subcategorized into two classes; Trematoda and Cestoidea. Clonorchis sinensis, a trematode parasite and Echinococcus granulosus, a cestoidean parasite are similar in the fact that they both are Platyhelminthes but these parasites differ in terms of their lifecycles and abilities to cause infection in humans.
Clonorchis sinensis belong to the class Trematoda. All trematodes are parasitic. Most trematodes have complex lifecycles having normally two or more hosts with the first host almost always being the mollusk. "Selection of the second intermediate host is less host-specific since cercaria are stimulated to swim by shadows and motion” (Eckroad). Echinococcus granulosus is of class Cestoidea. All cestoda are endoparasites requiring at least two hosts. The life cycle of Echinococcus granulosus includes dogs and other canines as the definit...
Distribution – The tongue eating louse is widespread. It can be found from the Gulf of California, to the north of the Gulf of Guayaquil, Ecuador. It has been found in waters from 2m to almost 60 m deep. This isopod is known to parasitize eight species of fish, all from two orders and four families. It can be found in seven species of order Perciformes: 3 snappers, 1 grunt, 3 drums, and one species of order Atheriniformes: 1 grunion. Females of this isopod have been found in the mouths of three species of snappers. It has also been seen in hosts from Costa Rica including the Colorado snapper, Lutjanus colorado and Jordan's snapper.
The meningeal worm is also known as the brain worm, or the deer worm. It frequently infects llamas and alpacas, but can infect other species as well like moose, elk, goats, and sheep. The meningeal worm is an internal parasite that is a part of the protostrongylidae family with the definitive host being the common white tailed deer. Even though they are the host, adult meningeal worms rarely cause clinical signs of disease in the deer. The white tail deer’s tolerance to infection from these worms is actually beneficial to the parasite because the white tail deer are the only species that will allow the worm to complete their life cycle. So alpacas and llamas are unsuitable hosts and that is why the meningeal worm is such a threat to them. It can cause varying degrees of damage to their central nervous system. “The cerebrospinal fluid tap is especially useful for diagnosing meningeal worm and ruling out other diseases.” (Whitehead, Bedenice 2009.) Ruling out other diseases helps to narrow down what could be ...
In some cases the eggs will get flushed out of the host. When this happens it releases miracidia that penetrate in to the snail. The snail is the intermediate host. When in the snail the organism uses asexual reproduction then development of cercariae. The cercariae can survive in...
Treponema pallidum is a Gram-negative bacterium that has a spiral shape (1). They are about 6 to 20um in length and 18-20um in diameter (1). Treponema pallidum can only survive within a host which makes them obligate internal parasites, meaning that outside a host this organism will die due to the absence of nutrients, exposure to oxygen and heat. Also since this organism can’t be grown on a culture medium, animal models are used to study T. pallidum (1). Treponema pallidum bacteria consist of an inner and outer membrane with a thin peptidoglycan cell wall lacking liposaccharides (1). They have a distinctive corkscrew motility with the aid of 6 endoflagellas (2). The specific classifications of Treponema pallidum are the following: Scientific name- Treponema pallidum, Common name- Syphilis. Treponema causes syphilis, yaws, and spinta. Borrelia causes Lyme disease and relapsing fever and Leptospira causing leptospirosis (5). What makes this microorganism special to the human population is that it causes infection to its host by entering the body through microscopic skin or mucous abrasions via direct personal contact with the lesions (sexual or kissing), blood transfusions, accidental bacterial inoculation, and transplacental passage (2). According to the CDC website there are 55,400 people diagnosed with Syphilis every year and 322 reported cases of congenital Syphilis in 2012 (6).
Epithelia tissue : Epithelial tissue, the type of tissue that lines the surfaces and cavities of your body 's organs, epithelia may be composed of several layers of cells called compound epithelia or just a single layer known as simple epithelia.
Merriam-Webster defines ‘parasite’ as ‘an organism that lives in or on another organism and benefits by deriving nutrients at the host 's expense’.
The pancreas can be divided into two sections when studying the histology. The pancreas has exocrine and endocrine functions, each with unique cell types. The exocrine pancreas serves to secrete digestive enzymes into the duodenum. Some of the specific enzymes and secreted substances are Proteases, lipase, amylase, bicarbonate, and water (Bowen, “Exocrine Secretions”). These enzymes are used to break down protein, fat, and carbohydrates respectively. The bicarbonate simply act as an acid buffer to prevent damage of the small intestine as the stomach acid must be neutralized. The enzymes are created in acinar cells and the bicarbonate is synthesized in epithelial cells surrounding pancreatic ducts (Bowen “Exocrine
Flatworms belong to the phylum Platyhelminthes. They have the simplest body plan of all bilaterally symmetrical animals. They are called flatworms because their bodies are compressed. The mouth is the only opening into the digestive cavity the flatworms have. Food is taken in through this hole and wastes are discharged also through this hole. Flatworms have a well-defined nervous, muscular, excretory, and reproductive system. The flatworm distributes the food it digests through a digestive tube that branches throughout all of its body parts. The fact that the worm’s body is flat serves many purposes. It allows the worm to hid in small spaces, to fit into the opening of other animals if the worm is parasitic, and it means that all the cells are close enough to the surface for exchange of oxygen and carbon dioxide with the environment (Meinkoth 399).
This disgusting worm parasite is spread by flies and mosquitoes. The adult worm spreads its larvae throughout the host’s lymphatic system and causes the lymph nodes to become clogged up. This also makes the tissue in the host’s body to swell up and create massive muscle deformations, otherwise known as elephantiasis. The elephantiasis mainly affects the legs and genitals. The disease also affects the eyes but that can be easily detected through close inspection but it commonly causes river blindness in the host. It’s been estimated that the parasite is one of the leading causes of blindness throughout the world.
Once your dog is infected with the parasitic worm the mosquito bites the next dog and the cycle continues. (Administration, Animal and Veterinary)
16. Describe two evolutionary consequences if the process of crossing over in meiosis ceased to occur. If crossing over in meiosis ceased to occur there would be less genetic variations and no diversity among a species. This would essentially mean that a species would not be able to adapt to an issue that could arise in the future, meaning that its species could potentially become extinct due to climate change or other arising events.
Every organ in the human body is composed of one or more tissues. The study of these tissues is known as histology. It is because of histology that the structure of organs can be researched and understood. Since organs are composed of tissues, it is important to understand each tissue type, their structure, their location, and their functions to better understand how each organ operates within the human body.
I chose to do this parasite due to my initial interest in seeing the removal of one of these worms. Seeing a live tape worm being drawn out of a body slowly is incredible fascinating. It is also a very tense situation because if the worm rips it can exponentially complicate the procedure and may even lead to death. This method is no longer used however and people simply take medication and the worm can then pass through their system. Although even today rural
T. pallidum is highly sensitive to oxygen and has a decreased ability to survive when not in human body temperature environments 1. The mode of transmission is through sexual contact or vertical transmission from the mother to the fetus. T. pallidum lacks the lipopolysaccharide which is the endotoxin normally present in gram negative bacteria1. The bacterium does produce many lipoproteins which are thought to prompt the inflammatory mediators through the recognition of toll-like receptors1. T. pallidum has a virulence factor of being highly motile due to its ability to propel itself forward by rotating on a longitudinal axis1. The spirochetes easily penetrate the skin or mucosal membranes and spread throughout the lymph nodes and then the blood circulation, affecting many parts in the body1.