Diseases caused by helminthes Questions in English

(C) $Wuchereria bancrofti$ is a digenetic parasite that completes its life cycle in two hosts.
The primary host is human,and the intermediate host is a blood-sucking insect,specifically the $Culex$ mosquito,which acts as the vector for transmitting the parasite.

(D) $Wuchereria$ $bancrofti$ is a filarial nematode that causes filariasis in humans.
The adult worms typically reside in the lymphatic vessels and lymph glands of the human host.
It is a viviparous nematode,meaning it gives birth to live young ones called microfilariae.

(A) $Ascaris$ (roundworm) is a metazoan parasite (a multicellular animal) that is transmitted through the ingestion of food or water contaminated with its eggs.
$Entamoeba$ is a protozoan parasite,not a metazoan.
$Guinea$ $worm$ ($Dracunculus$ $medinensis$) is transmitted through water containing infected copepods,but $Ascaris$ is the most classic example of a metazoan parasite transmitted via contaminated food/water in standard biology curricula.
$Plasmodium$ is a protozoan parasite.

(B) $Ascaris$ $lumbricoides$ is an intestinal parasite that causes ascariasis in humans.
The infection is primarily transmitted through the fecal-oral route.
Eggs of the parasite are passed in the feces of infected individuals and can contaminate soil,water,and food.
When a person consumes water or food contaminated with these infective eggs,the parasite enters the digestive system and completes its life cycle.
Therefore,the correct mode of transmission is through contaminated water and food.

(C) $Alcopar$ is an anthelmintic drug used in the treatment of $Ascariasis$.
$Ascariasis$ is caused by the roundworm $Ascaris$ $lumbricoides$.
Other drugs used for the treatment of $Ascariasis$ include $Antipar$,$santonin$,$chenopodium$ $oil$,and $Tetrachloroethylene$.

(A) Filariasis, also known as elephantiasis, is a chronic disease caused by parasitic filarial worms.
Specifically, the species $Wuchereria \text{ } bancrofti$ and $Wuchereria \text{ } malayi$ are the primary causative agents of this disease in humans.
These worms reside in the lymphatic vessels and lymph nodes, leading to inflammation and obstruction of the lymphatic system.
$Culex$ mosquitoes act as vectors that transmit the infection, but they do not cause the disease themselves.

(B) $Microfilariae$ are the larval stage of the parasitic nematode $Wuchereria$ $bancrofti$. These larvae are transmitted to humans through the bite of the female $Culex$ mosquito, which acts as the intermediate host and vector for the parasite.

(A) Ascariasis is an infection caused by the parasitic roundworm $Ascaris \text{ } lumbricoides$.
Chenopodium oil, derived from the plant $Chenopodium \text{ } ambrosioides$, has historically been used as an anthelmintic agent to treat intestinal worm infections, including ascariasis.
Paludrine is an antimalarial drug, and Terramycin is an antibiotic; therefore, they are not used for treating ascariasis.
Thus, the correct option is $A$.

(C) Elephantiasis, also known as filariasis, is a chronic condition characterized by the swelling of legs and other body parts.
It is caused by filarial worms belonging to the genus $Wuchereria$, specifically $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$.
These parasites are transmitted to humans through the bite of infected female $Culex$ mosquitoes.
Therefore, the correct option is $C$.

(D) The Hookworm,scientifically known as $Ancylostoma duodenale$,is a parasitic nematode that lives in the small intestine of humans and feeds on blood.
It has a direct life cycle,meaning it does not require an intermediate or secondary host to complete its development.
Therefore,the correct answer is $D$.

(D) $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$ are filarial worms that cause Filariasis,also known as Elephantiasis,in humans.
This disease is endemic in several parts of India,including states like Bihar,Uttar Pradesh,West Bengal,and parts of South India.
Since both Filariasis and Elephantiasis refer to the same condition caused by $Wuchereria$,and the disease is prevalent in multiple regions mentioned,the options provided are either incomplete or represent only partial geographical distributions.
However,in the context of standard biology questions,$Wuchereria$ is widely known to cause Filariasis (Elephantiasis) in various tropical and subtropical regions of India.

(D) $Ascaris$ lumbricoides is a parasitic nematode that causes ascariasis.
$1$. It is indeed more common in children due to their habits of playing in soil and poor hygiene.
$2$. It primarily affects the intestine and does not cause tonsillitis.
$3$. $A$ heavy infestation can involve a large number of worms,sometimes ranging from $500$ to $5000$.
$4$. Ascariasis is a parasitic infection that requires anthelmintic medication (such as albendazole or mebendazole) for treatment; it does not resolve spontaneously without medical intervention.
Therefore,the statement that the infection is cured without medication is false.

(C) The larvae of the filarial worm,known as microfilariae,exhibit a phenomenon called nocturnal periodicity. This means they migrate to the peripheral blood circulation of the human host specifically during the night. During the day,they retreat to the deeper blood vessels,particularly those in the lungs. This adaptation increases the likelihood of being ingested by the mosquito vector,which is typically active at night.

(A) Filariasis (also known as lymphatic filariasis) is a parasitic disease caused by microscopic, thread-like worms such as $Wuchereria$ $\text{bancrofti}$.
In India, the primary vector responsible for the transmission of $Wuchereria$ $\text{bancrofti}$ is the mosquito $Culex$ $\text{fatigans}$ (also known as $Culex$ $\text{quinquefasciatus}$).
These mosquitoes act as intermediate hosts and vectors, transmitting the infective larvae to humans during a blood meal.

(D) Filariasis, also known as elephantiasis, is a disease caused by parasitic worms known as helminths.
Specifically, it is caused by filarial worms such as $Wuchereria \, bancrofti$ and $Wuchereria \, malayi$.
These parasites are transmitted to humans through the bite of infected mosquito vectors.
Therefore, the correct option is $D$.

(A) Filariasis, also known as elephantiasis, is a parasitic disease caused by infection with microscopic, thread-like parasitic worms.
These worms belong to the phylum $Nematoda$ (roundworms).
Specifically, species such as $Wuchereria \text{ } bancrofti$ and $Brugia \text{ } malayi$ are the primary causative agents of this disease in humans.
Therefore, the correct option is $A$.

(C) The correct answer is $C$ (Hookworm).
$1$. Hookworm larvae (specifically $Ancylostoma$ $duodenale$ and $Necator$ $americanus$) are found in contaminated soil.
$2$. These larvae can actively penetrate the human skin,usually through the feet,when a person walks barefoot.
$3$. After penetrating the skin,they enter the bloodstream,migrate to the lungs,are coughed up and swallowed,and finally reach the small intestine to mature into adult worms.
$4$. In contrast,$Ascaris$ is typically ingested through contaminated food or water,and $Tapeworms$ are usually acquired by eating undercooked meat.

(B) The correct match is $Culex$ – $Filariasis/Elephantiasis$.
$Culex$ mosquitoes act as vectors for the transmission of $Wuchereria bancrofti$,the parasite responsible for $Filariasis$ (also known as $Elephantiasis$).
$Sandfly$ is the vector for $Leishmaniasis$ (Kala-azar),not $Plague$.
$Body Louse$ is the vector for $Epidemic Typhus$,not $Typhoid$ (which is caused by $Salmonella$ $typhi$ and transmitted via contaminated food/water).
$Housefly$ is a mechanical vector for diseases like $Cholera$ and $Dysentery$,whereas $Yellow Fever$ is transmitted by the $Aedes$ mosquito.

(B) Helminth diseases are caused by parasitic worms (helminths).
$A$ and $B$ refer to the same condition, which is caused by the filarial worms $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$.
$C$ (Polio) is a viral disease.
$D$ (Diphtheria) is a bacterial disease.
Therefore, Filariasis is the correct answer.

(C) $Chenopodium$ oil,derived from the plant $Chenopodium$ $ambrosioides$,contains the active compound ascaridole. It has historically been used as an anthelmintic agent to treat intestinal worm infections,specifically $Ascariasis$,which is caused by the roundworm $Ascaris$ $lumbricoides$.

(C) 'Enterobiasis' is an infection caused by the pinworm, $Enterobius \text{ } vermicularis$.
It is commonly known as pinworm infection or seatworm infection.
The parasite lives in the human intestine and lays eggs around the anus, causing itching.

(B) Cysticercosis is a parasitic tissue infection caused by the larval cysts of the tapeworm $Taenia \ solium$.
These larval cysts infect brain,muscle,or other tissue,and are a major cause of adult onset seizures in most low-income countries.
Humans become infected by ingesting eggs of $Taenia \ solium$ through contaminated food or water (fecal-oral route).
Therefore,the primary cause is the ingestion of contaminated food or water containing the eggs of the parasite.

(B) $Wuchereria bancrofti$ is a human parasitic roundworm that causes filariasis. The microfilariae are found mainly in the peripheral blood and can be found at peak amounts from $10 pm$ to $4 am$. They migrate between the deep and the peripheral circulation, exhibiting unique diurnal periodicity. During the day, they are present in the deep veins, and during the night, they migrate to the peripheral circulation. Therefore, to collect the filarial larvae, the peripheral blood should be collected during the night.

(D) Filariasis, also known as $Elephantiasis$, is caused by filarial worms, which are nematodes such as $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$.
Leprosy is caused by the bacterium $Mycobacterium$ $leprae$.
Poliomyelitis is a viral disease caused by the $Polio$ $virus$.
Amoebiasis is caused by the protozoan parasite $Entamoeba$ $histolytica$.

(D) $Ascaris$ is an intestinal parasite that causes ascariasis.
The infection is transmitted through the fecal-oral route.
Eggs of the parasite are excreted in the feces of infected persons and contaminate soil,water,and plants.
Consumption of contaminated water,vegetables,and fruits that contain the infective eggs leads to the infection in humans.

(B) Filariasis, also known as elephantiasis, is caused by filarial worms such as $Wuchereria$ $\text{bancrofti}$ and $Wuchereria$ $\text{malayi}$.
These organisms belong to the phylum Nematoda, which are classified as helminths.
The disease is transmitted to healthy individuals through the bite of female $Culex$ mosquitoes, which act as vectors.

(A) Filariasis,also known as elephantiasis,is caused by the nematode $Wuchereria$ $bancrofti$.
This pathogen is transmitted to humans through the bite of the $Culex$ mosquito (specifically $Culex$ $fatigans$ or $Culex$ $quinquefasciatus$).
In this disease,the lymphatic vessels are blocked,leading to chronic inflammation and massive enlargement of the affected organs,such as the legs or scrotum.

(D) Filariasis, also known as elephantiasis, is caused by filarial worms such as $Wuchereria$ $\text{bancrofti}$ and $Wuchereria$ $\text{malayi}$.
These parasites are transmitted to healthy individuals through the bite of infected female mosquitoes.
Specifically, the vector for the transmission of filarial worms is the female $Culex$ mosquito.
Male mosquitoes do not feed on blood and therefore cannot act as vectors for these diseases.

(D) Elephantiasis, also known as Filariasis, is a chronic condition characterized by the swelling of limbs and other body parts.
It is caused by filarial worms belonging to the genus $Wuchereria$, specifically $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$.
These parasites are transmitted to humans through the bite of infected female $Culex$ mosquitoes.
The worms reside in the lymphatic vessels of the human host, leading to inflammation and obstruction of lymph flow, which results in the characteristic swelling.

(C) Filariasis, also known as elephantiasis, is caused by filarial worms such as $Wuchereria$ $\text{bancrofti}$ and $Wuchereria$ $\text{malayi}$.
These parasites are transmitted to humans through the bite of infected female mosquitoes, primarily of the genus $Culex$, $Anopheles$, and $Mansonia$.
Therefore, the mosquito acts as the vector for the transmission of this disease.

(A) Filariasis, also known as elephantiasis, is a chronic condition caused by the parasitic filarial worms belonging to the genus $Wuchereria$ (specifically $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$).
These parasites are transmitted to humans through the bite of infected female mosquito vectors.
The worms reside in the lymphatic vessels of the lower limbs, leading to chronic inflammation and swelling.

(D) $Wuchereria bancrofti$ is the causative agent of filariasis (elephantiasis).
This parasite is transmitted to healthy individuals through the bite of female mosquitoes belonging to the genus $Culex$.
$Anopheles$ mosquitoes are vectors for malaria,while $Sand$ $fly$ transmits $Leishmania$ and $Tse-tse$ $fly$ transmits $Trypanosoma$.

(B) $Wuchereria$ $bancrofti$ is a filarial nematode that causes filariasis (elephantiasis) in humans.
Adult worms of $Wuchereria$ $bancrofti$ typically reside in the lymphatic vessels and lymph nodes of the human host.
They cause chronic inflammation of the organs in which they live for many years,usually the lymphatic vessels of the lower limbs,leading to swelling and deformity.

(C) $1$. Dengue fever is caused by the $Dengue$ virus.
$2$. Yellow fever is caused by the $Yellow$ $fever$ virus.
$3$. Filariasis (Elephantiasis) is caused by filarial worms like $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$. These are helminths,not viruses. They are transmitted to humans by the bite of female $Culex$ mosquitoes.
$4$. Chickenpox is caused by the $Varicella-zoster$ virus.
Therefore,the correct option is $C$.

(A) Elephantiasis, also known as filariasis, is a disease caused by filarial worms such as $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$. These worms belong to the phylum Nematoda. The disease is transmitted to humans through the bite of infected female mosquito vectors. Therefore, it is a helminthic infection caused by a worm.

(D) Filariasis, also known as elephantiasis, is caused by filarial worms such as $Wuchereria \text{ bancrofti}$ and $Wuchereria \text{ malayi}$.
These pathogens are transmitted to healthy individuals through the bite of female $Culex$ mosquitoes, which act as vectors.
Since the transmission of the parasite depends on the mosquito vector, the most effective way to prevent the disease is to control or eliminate the mosquito population.
Therefore, eliminating mosquitoes is the primary preventive measure.

(B) The life cycle of the filarial worm,$Wuchereria$ $bancrofti$,involves two hosts: humans and the female $Culex$ mosquito.
Inside the human body,the worms produce microfilariae.
When the mosquito bites an infected person,it ingests these microfilariae.
Within the mosquito,the microfilariae undergo development and transform into the third-stage infective larvae in approximately $10$ to $14$ days.
These infective larvae then migrate to the mosquito's proboscis and are transmitted to a new human host during the next blood meal.

(B) The causative agent of filariasis (elephantiasis) is the filarial worm, $Wuchereria \text{ bancrofti}$.
The life cycle of $Wuchereria$ involves two hosts: humans (definitive host) and female mosquitoes of the genus $Culex$ (intermediate host).
Specifically, the microfilariae (larval stage) present in the human blood are ingested by the female $Culex \text{ fatigans}$ mosquito during a blood meal.
Inside the mosquito, these larvae undergo development into the infective stage.

(C) The life cycle of $Wuchereria$ $bancrofti$ (the causative agent of filariasis) involves two hosts: humans and the female $Culex$ mosquito.
When the mosquito ingests blood containing microfilariae from an infected human,the microfilariae undergo development within the mosquito's body.
They pass through different larval stages $(L_1, L_2, L_3)$.
The $L_3$ stage is the infective stage.
This transformation from microfilariae to the infective $L_3$ larva typically takes about $10$ to $14$ days,but in the context of standard biological questions,$10$ days is the accepted duration for the completion of this development cycle in the vector.

(B) Filarial worms, such as $Wuchereria$ $\text{bancrofti}$ and $Wuchereria$ $\text{malayi}$, are the causative agents of filariasis (elephantiasis).
These parasites primarily reside in the lymphatic vessels and lymph nodes of the human body.
They cause chronic inflammation of the organs in which they live for many years, usually the lymphatic vessels of the lower limbs, leading to swelling and deformity.

(C) The correct answer is $C$. Filariasis (Elephantiasis) is caused by Wuchereria bancrofti or Wuchereria malayi.
$1$. The primary host is human, and the intermediate host is the female Culex mosquito (e.g., Culex fatigans).
$2$. Adult worms reside in the lymphatic vessels and lymph nodes of humans.
$3$. Filariasis is generally a chronic, debilitating disease characterized by swelling of limbs, but it is not typically considered a 'fatal' disease in the acute sense.
$4$. Adult filarial worms have a lifespan of approximately $5$ to $8$ years.

(C) The disease caused by the filarial worms, $Wuchereria$ \text{ bancrofti} and $Wuchereria$ \text{ malayi}, is known as filariasis or elephantiasis.
In this disease, the worms live for many years in the lymphatic vessels.
This leads to the blockage of the lymphatic vessels, which causes chronic inflammation and swelling of the organs in which they live, such as the limbs, genital organs, or breasts, often resulting in gross deformities.

(B) Filariasis is a disease caused by filarial worms such as $Wuchereria bancrofti$ and $Wuchereria malayi$.
These worms reside in the lymphatic vessels of the human lymphatic system for a long period.
This infestation leads to inflammation and obstruction in the lymphatic vessels,which is characteristic of the disease.
Therefore,the correct option is $B$.

(A) Elephantiasis, also known as filariasis, is caused by filarial worms such as $Wuchereria \text{ bancrofti}$ and $Wuchereria \text{ malayi}$.
These parasites live in the lymphatic vessels of the human body.
In chronic cases, the presence of these worms causes inflammation and blockage of the lymphatic vessels, leading to severe swelling in body parts like the legs, arms, and genital organs.
Therefore, Assertion $A$ is true, and Reason $R$ correctly explains why this swelling occurs.

(A) Elephantiasis, also known as filariasis, is caused by filarial worms such as $Wuchereria$ $bancrofti$ and $Wuchereria$ $malayi$.
These parasites typically infect the lymphatic vessels of the lower limbs.
As a result of chronic inflammation and obstruction of the lymphatic vessels, the skin and the underlying lymphatic tissues become thickened and hardened, leading to the characteristic swelling of the legs and genital organs.

(D) Elephantiasis (Filariasis) is caused by Wuchereria bancrofti.
$1$. The vector is the female Culex mosquito (Culex fatigans).
$2$. The infective stage for humans is the third-stage (infective) larvae.
$3$. These infective larvae reside in the proboscis (mouthparts) of the mosquito and enter the human skin during the blood meal.

(B) The filarial worms, such as $Wuchereria$ $\text{bancrofti}$ and $Wuchereria$ $\text{malayi}$, are responsible for filariasis (elephantiasis).
These parasites are ovoviviparous, meaning the eggs hatch inside the body of the female parent, and the larvae (microfilariae) are released directly into the host's blood or tissues.
Therefore, they are classified as ovoviviparous.

(D) Assertion $A$ is false because Elephantiasis (Filariasis) is a chronic condition that causes severe swelling and deformity, but it is not typically fatal.
Reason $R$ is true because the causative agents, Wuchereria bancrofti and Wuchereria malayi, live in the lymphatic vessels and lymph nodes of the human body.
Therefore, $A$ is false and $R$ is true.

(B) The adult filarial worm,such as $Wuchereria$ $bancrofti$,which causes filariasis (elephantiasis),is known to have a long lifespan within the human lymphatic system. Scientific studies indicate that these adult worms can survive in the human host for approximately $5$ to $8$ years,during which they continuously release microfilariae into the bloodstream.