Helminths, Arthropods, And Prions! Trivia

Nematodes are another name for roundworms. This term is commonly used in scientific literature and discussions to refer to this group of worms. The other options, platyhelminths, flukes, and tapeworms, are different types of worms and not synonymous with roundworms.

Laboratory diagnosis of a helminths infection examines stool for the presence of ova and parasites. This is because helminths, which are parasitic worms, primarily reside in the gastrointestinal tract. By examining the stool, healthcare professionals can identify the presence of helminth eggs (ova) or adult worms, as well as other parasitic organisms. Blood, urine, and tissue samples are not typically used for diagnosing helminth infections, as they do not provide direct evidence of the parasites residing in the digestive system.

Helminths is the correct answer because it is a term used to describe all groups of parasitic worms. This includes flukes, nematodes, and platyhelminths. Helminths are a diverse group of organisms that can infect humans and animals, causing a wide range of diseases. They can be found in various parts of the body, such as the intestines, liver, and blood. Therefore, helminths is the most appropriate term to encompass all types of parasitic worms.

Taeniasis refers specifically to an infection with the adult tapeworm in the gut of the definitive host. It is a parasitic infection caused by the genus Taenia, which includes tapeworm species such as Taenia solium and Taenia saginata. These tapeworms can infect humans when they consume undercooked or raw contaminated meat. Once ingested, the tapeworms establish themselves in the intestines and can cause symptoms such as abdominal pain, diarrhea, and weight loss. Treatment typically involves medication to kill the tapeworm and its eggs.

Mosquitoes, fleas, and ticks are considered to be arthropods because they belong to the phylum Arthropoda. Arthropods are a diverse group of invertebrates that have jointed limbs, segmented bodies, and an exoskeleton. They include insects, spiders, crustaceans, and other related organisms. Mosquitoes, fleas, and ticks are all examples of arthropods that feed on human blood and tissue fluids as part of their life cycle.

Helminths are classified as multicellular metazoa because they are parasitic worms that have complex, multicellular structures. Unlike single-celled protozoa or single-celled metazoa, helminths have specialized tissues and organs that allow them to carry out various functions necessary for their survival. This classification distinguishes them from other microscopic organisms and highlights their unique characteristics as multicellular organisms.

Prion diseases are characterized by the misfolding of normal cellular prion proteins into abnormal infectious forms. These abnormal prion proteins can accumulate in the brain, causing neurodegeneration. Unlike other infectious diseases, prion diseases do not elicit a strong immune response, and there are no significant circulating antibodies present. This lack of immune system involvement is one of the reasons why prion diseases are difficult to diagnose and treat effectively. Therefore, the statement that there are no significant circulating antibodies in prion disease, and thus little involvement with the immune system, is true.

Nematodes, or roundworms, have unsegmented tube-like bodies that have a pseudocoelum. The pseudocoelum acts as a hydrostatic skeleton, providing rigidity to the body. This allows nematodes to maintain their shape and move efficiently.

In the helminths life cycle, a definitive host is one in which the sexual cycle occurs (or the adult is present). This means that the definitive host is the host in which the adult stage of the helminth is found and where sexual reproduction takes place. The other options, such as intermediate, asexual, or initial, do not accurately describe the host in which the sexual cycle occurs.

D. latum (fish tapeworm) can deplete the host of vitamin B12 leading to megaloblastic anemia. Vitamin B12 is essential for the production of healthy red blood cells, and its deficiency can result in the formation of abnormally large and immature red blood cells. The fish tapeworm absorbs vitamin B12 from the host's intestines, leading to a decrease in the available vitamin B12 for the host's own use. This depletion can ultimately result in megaloblastic anemia, characterized by fatigue, weakness, and shortness of breath.

Mutations in the gene encoding PrPc (cellular prion protein) could lead to the spontaneous appearance of prions in the body. PrPc is the normal, non-infectious form of the prion protein found in healthy individuals. However, when misfolded, it can convert into PrPsc (scrapie prion protein), which is the infectious form associated with prion diseases. Mutations in the gene encoding PrPc can disrupt the normal folding process, leading to the misfolding and accumulation of PrPsc, ultimately resulting in the spontaneous appearance of prions in the body.

unlikely as none of the hundreds of infants born to mothers with kuru developed the disease

Normal is alpha helix.
Abnormal is beta-pleated sheet.
The pathogenic form increases in amount by inducing conformational change

vCJD (variant Creutzfeldt-Jakob Disease) is the correct answer because it is a spongiform encephalopathy that can be transmitted from cattle to humans. This disease is believed to be caused by the consumption of meat from cattle infected with bovine spongiform encephalopathy (BSE), also known as mad cow disease. vCJD affects the brain, causing rapid and progressive neurological symptoms, including dementia, muscle stiffness, and loss of coordination. It is a rare and fatal disease that has been linked to the consumption of contaminated beef products.

Kuru is a prion disease that is transmitted through cannibalism, particularly the consumption of human brains. It is commonly found among the Fore people in Papua New Guinea, where the practice of eating deceased family members as a funeral ritual was prevalent. Kuru affects the brain and nervous system, leading to symptoms such as tremors, difficulty walking, and eventually death. The consumption of infected human brain tissue by zombies would put them at risk of contracting this disease.

Schistosomes are parasitic worms that infect the blood vessels of humans. They cause a disease called schistosomiasis, which is one of the most important flukes. The worms lay their eggs in the blood vessels, and when the eggs hatch, the larvae can travel to various organs in the body through the bloodstream. Therefore, the correct answer is "blood" as schistosomes primarily infect the blood in humans.