ZEB Chpt 3(1/2)Pg.65-80 And BIO 152 Chpt 24 Flashcards
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Q
- Helminths that affect humans belong to which two phyla a) Platyhelminthes and Annelida b) Platyhelminthes and Nematelminthes c) Nematelminthes and Cnidaria d) Cnidaria and Platyhelminthes
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Answer b) Platyhelminthes and Nematelminthes Explanation These are the two major phyla that include helminths (worms) affecting humans Platyhelminthes (flatworms like trematodes and cestodes) and Nematelminthes (roundworms)
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Q
- What are the two subclasses of Trematoda a) Aspidogastrea and Cestoda b) Aspidogastrea and Digenea c) Digenea and Monogenea d) Cestoda and Monogenea
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Answer b)monogenea and Digenea Explanation Trematoda is divided into monogenea (less parasitic) and Digenea (includes most parasitic flukes)
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Q
- What is the first host in the life cycle of almost all trematodes a) Fish b) Birds c) Molluscs d) Humans
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Answer c) Molluscs Explanation Molluscs usually snails serve as the intermediate hosts for trematodes where larval development begins
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Q
- Which of the following is NOT a characteristic of Aspidogastrea a) They have no acetabulum b) They are commonly digenetic c) Reproduction in water is rare d) They primarily infect molluscs
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Answer b) They are commonly digenetic Explanation Aspidogastrea are monogenetic requiring only one host unlike digenetic trematodes like Digenea
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Q
- What is the name of the larval form that exemplifies the remarkable life history of asexual reproduction in trematodes a) Miracidium b) Sporocyst c) Redia d) Cercaria
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Answer a) Miracidium Explanation Miracidium is the first larval stage capable of asexual reproduction in its snail host
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Q
- What is the definitive host in the life cycle of Leucochloridium paradoxum a) Snail b) Bird c) Fish d) Mollusc
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Answer b) Bird Explanation Birds are the definitive hosts where sexual reproduction occurs
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Q
- Which stage of the trematode life cycle is described as a transparent larvae a) Miracidia b) Sporocyst c) Redia d) Cercaria
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Answer a) Miracidia Explanation The miracidium stage is free-swimming and transparent seeking its snail host
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Q
- Where in the snail’s body do redia move to mature into cercaria a) Digestive gland b) Brood sac c) Central body d) Foot
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Answer b) Brood saExplanation Redia move to the brood sac for further development into cercaria
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Q
- Which genus of flukes has collars of spines behind the oral sucker a) Gastrodiscoides b) Echinostoma c) Paragonimus d) Clonorchis
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Answer a) Gastrodiscoides Explanation These spines aid in attachment to the host
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Q
- In which host does the cercariae of the genus Paragonimus encyst a) Molluscs b) Crustaceans c) Insects d) Fish
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Answer b) Crustaceans Explanation Cercariae encyst in crustaceans like crabs or crayfish
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Q
- Where are the testes located in flukes of the genus Opisthorchis a) Side by side behind the ovary b) In tandem behind the ovary c) In front of the ovary d) Within the ovary
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Answer b) In tandem behind the ovary Explanation The testes of Opisthorchis are arranged in tandem (one behind the other) which is a distinguishing characteristic
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Q
- Which family of flukes is characterized as minute flukes a) Echinostomatidae b) Heterophyidae c) Opisthorchiidae d) Dicrocoeliidae
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Answer b) Heterophyidae Explanation Heterophyidae flukes are small-sized intestinal parasites
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Q
- The excretory system of Heterophyes consists of what a) A single excretory pore b) Two intestinal caeca flame cells collecting tubules and an excretory pore c) Flame cells and an excretory pore d) Two intestinal caeca and an excretory pore
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Answer b) Two intestinal caeca flame cells collecting tubules and an excretory pore Explanation This complex excretory system is typical of trematodes for osmoregulation and waste removal
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Q
- Intestinal and liver trematodes can be broadly divided into two groups What are they a) Those that reside in the bile ducts and those that inhabit the liver b) Those that reside in the liver and those that inhabit the intestines c) Those that reside in the intestines and those that inhabit the bile ducts d) Those that reside in the blood vessels and those that reside in the lungs
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Answer c) Those that reside in the intestines and those that inhabit the bile ducts Explanation Trematodes are classified based on their habitat in the host’s body
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Q
- What is the intermediate host of Fasciola buski a) Fish b) Aquatic plants c) Snails d) Crabs
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Answer c) snails Explanation Encysted metacercariae of snails are found on aquatic plants consumed by humans
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Q
- What is the morphology of adult trematodes worms a) Round b) Flat c) Cylindrical d) Spiral
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Answer b) Flat Explanation Adult trematodes are dorsoventrally flattened earning them the name flatworms
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Q
- How can adult worms be readily differentiated a) By their size b) By their color c) By their shape and morphology d) By the host they infect
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Answer c) By their shape and morphology Explanation The shape and structural details like spines and suckers help identify species
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Q
- Where are eggs in the life cycle pattern for intestinal flukes found a) Urine b) Feces c) Blood d) Sputum
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Answer b) Feces Explanation Intestinal fluke eggs are expelled from the host in feces
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Q
- Where does the metacercariae encyst in the life cycle pattern for intestinal flukes a) Intestines of humans b) Vegetation or in fish crab or crayfish c) Lungs of humans d) Water
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Answer b) Vegetation or in fish crab or crayfish Explanation Metacercariae encyst on vegetation or intermediate hosts before being ingested by humans
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Q
- How do cercariae emerge a) They are ingested b) They are inhaled c) They develop into progangani d) They are released from the snail into water
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Answer d) They are released from the snail into water Explanation Cercariae actively leave the snail to seek their next host in water
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Q
- Why is the zinc sulphate floatation technique not recommended for concentrating trematode eggs? a) The eggs are too dense. b) The egg shell is very fragile and may break at the concentration of the salt. c) The eggs are too small. d) The eggs are not buoyant.
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Explanation: Zinc sulphate floatation technique is not recommended because the egg shell of trematode eggs is fragile and the concentration of zinc sulphate may cause the eggs to break leading to inaccurate results.
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Q
- How can adult worms be detected in a patient undergoing treatment for a heavy infection? a) Urine sample b) Blood sample c) Sputum sample d) Feces
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Explanation: Adult worms can be detected through fecal examination as the eggs or worms may be passed out in the feces during heavy infections.
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Q
- Which of the following is a characteristic of schistosomes that is different from other trematodes? a) They are hermaphrodites. b) They are not hermaphrodites. c) Their life cycle is the same as other trematodes. d) The infection occurs by ingestion.
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Explanation: Schistosomes are dioecious (not hermaphroditic) unlike other trematodes that are typically hermaphrodites.
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Q
- How does the infection by the larval form the cercaria occur in schistosomes? a) Through skin penetration b) Through ingestion c) Through inhalation d) Through contact with contaminated water
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Explanation: Schistosome infection occurs when cercariae penetrate the skin of the host.
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30. Where do adult worms of schistosomes live? a) Liver b) Intestines c) Lungs d) Blood vessels
Explanation: Adult schistosome worms reside in the blood vessels of the host particularly in the venules of the intestines or bladder.
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31. Which species of Schistosoma causes urinary schistosomiasis? a) Schistosoma mansoni b) Schistosoma japonicum c) Schistosoma haematobium d) Schistosoma mekongi
Explanation: Schistosoma haematobium is the species responsible for urinary schistosomiasis affecting the bladder and urinary tract.
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32. In what bodily fluid are eggs of schistosomes passed? a) Feces or urine b) Blood c) Sputum d) Saliva
Explanation: Schistosome eggs are passed in the feces or urine depending on the species.
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33. What is the name of the larval stage that penetrates snail host in the life cycle of schistosomes? a) Miracidium b) Cercariae c) Sporocyst d) Redia
Explanation: The miracidium are the free-swimming larval stage of schistosomes that penetrate the snail host.
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34. What characteristic of the cercariae helps them to penetrate human skin? a) They have a tail. b) They have a bifurcated tail. c) They are very small. d) They release enzymes.
Explanation: The enzyme activity of cercariae aids in and helps them penetrate human skin.
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35. Where in the human body do the cercariae of Schistosoma finally enter a blood vessel and mature into an adult? a) Heart b) Liver sinusoids c) Lungs d) Brain
Explanation: The cercariae enter the blood vessels through the liver sinusoids where they mature into adult worms.
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36. How do the adult worms of Schistosoma reside in the venules? a) Singly b) In groups c) In pairs d) It varies depending on the species.
Explanation: Adult schistosome worms are usually found in pairs in the venules with the female residing in the male's gynecophoric canal.
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37. Where are the eggs of Schistosoma mansoni deposited? a) Veins of the bladder b) Intestine c) Liver d) Lungs
Explanation: Schistosoma mansoni eggs are deposited in the intestinal venules and later passed out in the feces.
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38. Where are the eggs of Schistosoma haematobium deposited? a) Veins of the bladder b) Intestine c) Liver d) Lungs
Explanation: Schistosoma haematobium eggs are deposited in the veins of the bladder and passed out through urine.
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39. What is the morphology of Schistosoma adult worms? a) Round b) Cylindrical c) Flat leaf-like d) Spiral
Explanation: Adult Schistosoma worms have a flat leaf-like morphology that allows them to fit within the venules.
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40. What is a distinctive feature of male Schistosoma worms? a) They have a gynecophoric canal. b) They have testes. c) They have a ventral sucker. d) Their body is folded to form a ventral gynaecophoric canal.
Explanation: Male Schistosoma worms have a folded body that forms a gynecophoric canal to house the female during mating.
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41. When are eggs of Schistosoma released immature? a) When first laid b) After a few days c) When they reach the liver d) When they reach the intestines
Explanation: Schistosoma eggs are released immature and only develop later in the environment.
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42. What is contained in the mature miracidium of Schistosoma? a) A tail b) A shell c) A fully developed embryo d) Eggs
Explanation: The mature miracidium contains a fully developed embryo that is capable of infecting the snail host.
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43. What helps in differentiating the eggs of Schistosoma? a) Size of the egg b) Shape of the egg c) Position of the spine d) All of the above
Explanation: Differentiating Schistosoma eggs relies on their size shape and position of the spine.
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44. What is contained within the Schistosoma egg when passed out in urine or feces? a) An immature embryo b) A fully developed miracidium c) A cercaria d) A sporocyst
The correct answer is a) An immature embryo.
Schistosoma eggs, when passed out in urine or feces, contain an immature embryo. These eggs are released by adult female Schistosoma worms and are passed out of the host's body. Once they reach water, the eggs hatch, and the immature embryo inside develops into a miracidium, which is the next larval stage. The miracidium then swims in search of an intermediate host (usually a snail) to continue its life cycle.
Here’s the reasoning for each option:
a) An immature embryo: This is correct because Schistosoma eggs initially contain an immature embryo, which will later hatch into a miracidium.
b) A fully developed miracidium: Incorrect, as the miracidium is not fully developed inside the egg. It hatches and develops after the egg reaches water.
c) A cercaria: Incorrect, as the cercaria is a later stage in the life cycle that emerges from the snail after the miracidium has infected it.
d) A sporocyst: Incorrect, because the sporocyst is formed inside the snail, not within the egg.
Thus, Schistosoma eggs initially contain an immature embryo, which will hatch and continue the lifecycle in a freshwater environment.
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45. Which diagnostic method can be used to detect Schistosoma haematobium eggs that may not be seen in stool? a) Urine examination b) Rectal biopsy c) Blood test d) Sputum examination
Explanation: Rectal biopsy may be used to detect Schistosoma haematobium eggs in cases where they are not detected in stool samples.
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46. How is a viable miracidium indicated? a) By the presence of eggs b) By the presence of adult worms c) By the flickering of flame cells d) By the presence of granulomas
Explanation: The flickering of flame cells is an indication of a viable miracidium.
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47. How many phases can the clinical symptoms of schistosomiasis be divided into? a) Two b) Three c) Four d) Five
Explanation: The clinical symptoms of schistosomiasis are typically divided into three phases: acute subacute and chronic.
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48. When does Katayama fever occur in infections with Schistosoma mansoni and Schistosoma japonicum? a) Immediately after infection b) About a month after infection c) Several months after infection d) Years after infection
Explanation: Katayama fever occurs about a month after infection during the acute phase of schistosomiasis.
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49. What is the characteristic symptom of Schistosoma haematobium? a) Hepatosplenomegaly b) Diarrhea c) Hematuria d) Fever
Explanation: Hematuria (blood in urine) is a characteristic symptom of Schistosoma haematobium infection.
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50. What facilitates the passage of Schistosoma eggs on the lumen of the bladder or the intestine? a) Their size b) Their shape c) A number of enzymes d) Blood flow
Explanation: The passage of Schistosoma eggs is facilitated by a number of enzymes that help break down tissue barriers in the bladder or intestine.
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1. The concept of health can be understood differently depending on perspective. For a pathologist health primarily focuses on: a. Sound mind and normal function of the body b. Normal biochemical values c. Correct existence of genetic potential d. Normal cellular make-up
Explanation: The text explicitly states that "To a Pathologist it means normal cellular make-up."
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2. Disease can be simply defined as: a. A state of complete physical mental and social well-being b. Absence of difficulty c. An abnormal condition a disorder of a structure or function that affects part or all of an organism d. Suffering and its study
Explanation: The text states that "Disease = absence of difficulty." While the other options touch upon aspects of disease or health they don't represent the simplified definition provided in the text.
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3. What is the core focus of the study of pathology? a. The causes of suffering b. The biological agent that causes a disease or illness c. The absence of difficulty d. The mechanisms by which an infection leads to disease
Explanation: Pathology is specifically defined as "the study of the cause of disease."
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4. Which of the following is a defining characteristic of a pathogen? a. All pathogens are microorganisms b. They are capable of causing disease c. They always produce toxins d. They are solely responsible for virulence
Explanation: The text emphasizes that pathogens are "microbes that are capable of causing disease." It's important to note that not all microorganisms are pathogenic.
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5. Virulence factors contribute to a pathogen's ability to: a. Reproduce within a host b. Evade the host's immune system c. Cause disease in a host d. Be transmitted between hosts
Explanation: Virulence factors including toxins give reasonable contribution to cause the disease. They enhance the pathogen's capacity to inflict harm on the host.
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6. The measurement of a pathogen's ability to cause disease in a host is known as: a. Pathogenicity b. Infectivity c. Virulence d. Resistance
Explanation: The passage clearly distinguishes between pathogenicity and virulence. Virulence is the "measurement of the ability to cause a disease in host."
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7. When determining the nature of a disease two primary factors are considered crucial. These are: a. The size and shape of the pathogen b. The nature of the pathogen and the genetic makeup of the host c. The host's diet and environmental factors d. The presence of antibodies and white blood cells
Explanation: The text explicitly mentions that "To cause a disease two factors are important i.e. the nature of the pathogen and the nature of the host."
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8. The Lethal Dose (LD50) is an important measure in microbiology. What does it represent? a. The amount of pathogen needed to kill all test subjects b. The highest dose of a substance that does not cause death c. The median lethal dose of the substance required to kill 50% of the test population d. The time taken for a pathogen to kill 50% of its host cells
Explanation: LD50 is defined as the "median lethal dose of the substance required to kill 50% of the test population." It's a crucial parameter for assessing the virulence of a pathogen.
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9. A virus is fundamentally characterized as: a. A single-celled organism b. An obligate intracellular nucleic acid molecule in a protein coat c. A prokaryotic cell lacking a nucleus d. A free-living organism capable of independent replication
Explanation: The provided text states that a virus is "an obligate intracellular nucleic acid molecule in a protein coat." This highlights the fact that viruses are not independent living organisms.
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10. Which of the following is NOT a component of a virion (virus particle)? a. Cell membrane b. Nucleic acid c. Protein coat (Capsid) d. Envelope (in some viruses)
Explanation: While some viruses possess an envelope a cell membrane is not a typical component of a virion. Virions consist of a nucleic acid core a protein capsid and sometimes an envelope derived from the host cell membrane.
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11. In the context of viral replication what does the term "provirus" (prophage) refer to? a. A newly assembled virus particle b. A virus in its lytic phase c. The viral genome integrated into the host genome d. The process of viral entry into a host cell
Explanation: The text clarifies that a provirus or prophage is the "viral genome integrated into the host genome." This integrated state is characteristic of the lysogenic cycle.
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12. The lytic cycle of viral replication involves several distinct steps. Which of the following is the initial step in this process? a. Replication b. Assembly c. Adsorption or attachment d. Release
Explanation: The first step in the lytic cycle is "adsorption or attachment" of the virus to the host cell. This is a critical step that allows the virus to gain entry.
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13. During the uncoating stage of viral replication what key event takes place? a. The virus attaches to the host cell b. The virus replicates its genetic material c. New virus particles are assembled d. The viral genetic material is released into the host cell
Explanation: Uncoating is the process where the "viral genomic nucleic acid is released into the host cell." This release allows the viral genetic material to take control of the host's cellular machinery.
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14. In the assembly stage of viral replication: a. The virus enters the host cell b. The viral genome integrates into the host genome c. The cell come together to form new viruses d. The newly formed viruses kill the host cell
Explanation: The assembly stage is where "the particles of the virus created by the cell come together to form new viruses." This step marks the creation of complete viral particles.
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15. The final stage of the lytic cycle resulting in the liberation of new virions is called: a. Replication b. Lysis c. Release d. Uncoating
Explanation: The final stage is "release" where "the newly formed viruses kill the cell by lysing thereby releasing new virions" to infect other cells.
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16. Which of the following is a DNA virus that can lead to severe liver damage and potentially liver cancer? a. Hepatitis B b. Measles c. Mumps d. Polio
Explanation: The table identifies Hepatitis B as a DNA virus associated with liver disease. It can cause chronic infection and significantly increase the risk of liver cancer.
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17. Which virus is responsible for Acquired Immunodeficiency Syndrome (AIDS)? a. Human Immunodeficiency Virus (HIV) b. Paramyxovirus c. Rhinovirus d. Picornavirus
Explanation: AIDS is caused by the Human Immunodeficiency Virus (HIV). This virus attacks the immune system making individuals highly susceptible to opportunistic infections and certain cancers.
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18. Which of the following diseases is characterized by painful swelling of the parotid gland? a. Hepatitis B b. Measles c. Mumps d. Common cold
Explanation: The table indicates that Mumps caused by the Paramyxovirus leads to "Painful swelling of the parotid gland."
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19. What type of infection is the common cold categorized as? a. Blood infection b. Droplet infection c. Contact infection d. Airborne infection
Explanation: The common cold caused by the Rhinovirus is transmitted through droplet infection. This occurs when an infected person coughs or sneezes releasing tiny droplets containing the virus.
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20. Polio a disease that can lead to paralysis is caused by which type of virus? a. DNA virus b. RNA virus c. Retrovirus d. Bacteriophage
Explanation: The table lists Polio as being caused by a Picornavirus which is an RNA virus. This virus can affect the nervous system and in some cases lead to paralysis.
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21. The term "prokaryote" originates from Greek words where "Pro" means "before" and "karyon" means a. Cell b. Life c. Nucleus d.Membrane
Explanation: The text explains that the term "prokaryote" comes from "Pro" meaning "before" and "karyon" meaning "nucleus". This highlights a fundamental characteristic of prokaryotic cells: they lack a true nucleus.
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22. Which of the following is a distinctive feature of prokaryotic organisms? a. They have a well-defined nucleus b. They are multicellular c. They possess membrane-bound organelles d. They lack a nuclear membrane
Explanation: Prokaryotes unlike eukaryotic cells "lack a nuclear membrane" to enclose their genetic material.
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23. The shape of the bacterium Vibrio cholerae responsible for cholera is: a. Rod-shaped b. Spherical c. Comma shaped d. Spiral
Explanation: The table specifies that Vibrio cholerae is "comma shaped". This distinct morphology is one of its identifying characteristics.
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24. Typhoid fever is primarily spread through: a. Contaminated food or water b. Droplet infection c. Contact with an infected person d. Airborne transmission
Explanation: The mode of transmission for typhoid fever is listed as "Contaminated food or water (faecal-oral-route)".
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25. Mycobacterium tuberculosis the causative agent of tuberculosis is characterized as: a. Comma shaped b. Spherical c. Rod shaped d. Spiral
Explanation: Mycobacterium tuberculosis is described as a "rod shaped" bacterium. This morphology is typical of many bacterial species.
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26. The primary mode of transmission for tuberculosis is: a. Contaminated food or water b. Droplet infection c. Contact with an infected person d. Airborne transmission
Explanation: The text states that tuberculosis is spread through "Droplet infection." This occurs when an infected person coughs or sneezes releasing droplets containing the bacteria.
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27. Tetanus a condition characterized by muscle spasms is caused by which bacterium? a. Vibrio cholerae b. Salmonella typhi c. Mycobacterium tuberculosis d. Clostridium tetani
Explanation: The table clearly indicates that Clostridium tetani is responsible for tetanus.
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28. How is tetanus typically contracted? a. Contaminated food or water b. Droplet infection c. Contact with a contaminated wound d. Airborne transmission
Explanation: Tetanus is acquired through "Contaminated wound". The bacteria commonly found in soil enter the body through breaks in the skin.
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29. The bacterium responsible for whooping cough a highly contagious respiratory infection is: a. Vibrio cholerae b. Salmonella typhi c. Clostridium tetani d. Bordetella pertussis
Explanation: The table identifies Bordetella pertussis as the causative agent of whooping cough. This bacterium infects the respiratory tract leading to severe coughing spells.
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30. What is the primary mode of transmission for whooping cough? a. Contaminated food or water b. Droplet infection c. Contact with an infected person d. Airborne transmission
Explanation: Whooping cough is spread via "Droplet infection." Similar to other respiratory infections it can be transmitted when an infected person coughs or sneezes.
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31. Gastro-enteritis (Salmonellosis) is caused by bacteria of the genus: a. Vibrio b. Mycobacterium c. Clostridium d. Salmonella
Explanation: The table points out that Salmonella spp. is the cause of gastro-enteritis also known as salmonellosis.
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32. What is the typical shape of the bacteria Salmonella spp.? a. Comma shaped b. Spherical c. Rod shaped d. Spiral
Explanation: Salmonella spp. are described as "rod-shaped" bacteria.
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33. How is gastro-enteritis (Salmonellosis) usually contracted? a. Contaminated food or water b. Droplet infection c. Contact with an infected person d. Airborne transmission
Explanation: Gastro-enteritis is primarily transmitted through "Contaminated food or water". This occurs when food or water sources become contaminated with the Salmonella bacteria.
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34. A key structural difference between Gram-positive and Gram-negative bacteria lies in their: a. Cell wall b. Genetic material c. Shape d. Motility
Explanation: Figure 24.2 illustrates the "Structural differences in the cell wall of Gram positive and Gram negative bacteria."
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35. Fungi are categorized as: a. Prokaryotic organisms b. Eukaryotic organisms c. Viruses d.Bacteria
Explanation: The text explicitly states that fungi are "a large group of eukaryotic organisms." This places them in a different kingdom than bacteria which are prokaryotes.
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36. Yeasts a type of fungi are characterized by their: a. Multicellular structure b. Unicellular structure c. Ability to form hyphae d. Production of spores
Explanation: Yeasts are described as "unicellular fungi" in contrast to molds which are multicellular.
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37. Molds another type of fungi form: a. Single-celled structures b. Multicellular structures c. Spores but not hyphae d. Hyphae that remain unbranched
Explanation: Molds unlike yeasts are "multicellular fungi" that grow as long branching filaments called hyphae.
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38. Dimorphic fungi display a remarkable characteristic. They can: a. Reproduce both sexually and asexually b. Form both spores and hyphae c. Change from the yeast form to the mold form d. Live in both aquatic and terrestrial environments
Explanation: Dimorphic fungi can switch between two forms "they have two forms). Dimorphic fungi can change from the yeast form to the mold form." This adaptability allows them to thrive in diverse environments.
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39. Which of the following is a pathogenic fungi known to cause liver damage edema and necrosis? a. Candida albicans b. Trichophyton spp. c. Microsporum spp. d. Aspergillus flavus
Explanation: The table lists Aspergillus flavus as the pathogenic fungi responsible for aflatoxicosis a condition that can cause "Haemorrhage necrosis of the liver edema".
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40. Candida albicans is a common fungi known to cause: a. Athlete's foot b. Ringworm c. Candidiasis d. Vaginal yeast infection
Explanation: The table indicates that Candida albicans causes candidiasis. This fungal infection can affect various parts of the body including the mouth skin and genitals.
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51. Which species of Schistosoma may lead to blood-stained feces in infections? a) Schistosoma haematobium b) Schistosoma mansoni c) Schistosoma japonicum d) Schistosoma mekongi
Explanation: Schistosoma mansoni primarily affects the intestinal tract leading to blood-stained feces as a symptom.
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52. What happens to the tissues where Schistosoma eggs are deposited? a) They become calcified. b) They become inflamed and thickened. c) They become necrotic. d) They become fibrous.
Explanation: Egg deposition triggers an immune response causing inflammation and thickening of surrounding tissues.
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53. What is formed around the eggs deposited in the tissues in Schistosoma infections? a) Cysts b) Abscesses c) Granulomas d) Tumors
Explanation: Granulomas form as the immune system isolates the eggs preventing further damage to tissues.
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54. Cerebral symptoms are commonly seen in infections with which species of Schistosoma? a) Schistosoma japonicum b) Schistosoma mansoni c) Schistosoma haematobium d) Schistosoma mekongi
Explanation: Schistosoma japonicum has a broader egg dispersal and is more likely to cause cerebral symptoms.
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55. Which of the following is NOT a laboratory diagnosis for Schistosomiasis? a) Detection of eggs in urine feces and rectal or bladder biopsy b) Serological diagnosis c) Blood culture d) Of host) High titres continue to exist even after treatment
Explanation: Blood cultures are not used in diagnosing Schistosomiasis as the parasite does not multiply in the blood.
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56. What is the current drug of choice for the treatment of schistosomiasis? a) Praziquantel b) Albendazole c) Metronidazole d) Ivermectin
Explanation: Praziquantel is highly effective against all species of Schistosoma.
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57. What is the best-known lung fluke affecting humans? a) Fasciola hepatica b) Clonorchis sinensis c) Paragonimus westermani d) Schistosoma mansoni
Explanation: Paragonimus westermani is widely recognized as the primary lung fluke affecting humans.
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58. Which region does Paragonimus westermani have the widest geographical range? a) Africa b) North America c) Far East d) South America
Explanation: Paragonimus westermani is predominantly found in East and Southeast Asia.
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59. How is Paragonimus westermani infection acquired? a) By drinking contaminated water b) By contact with infected snails c) By ingestion of raw or insufficiently cooked crayfish or freshwater crabs d) By inhalation of contaminated air
Explanation: Humans ingest the encysted larvae by eating raw or undercooked crustaceans.
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60. What is the encysted metacercarial stage of Paragonimus westermani called? a) 'Folken crab' b) 'Rediae' c) 'Cercariae' d) 'Miracidia
' Explanation: 'Folken crab' refers to the encysted larval stage found in intermediate crustacean hosts.
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61. How long does it take for Paragonimus westermani eggs to hatch in water? a) 24 hours b) A few days c) A week d) 2-3 weeks
Explanation: The eggs require 2-3 weeks in freshwater to develop and hatch into miracidia.
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62. What is the final host for Paragonimus westermani? a) Snail b) Crab c) Fish d) Man
Explanation: Humans are the definitive hosts where the adult flukes reside in the lungs.
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63. How many generations of rediae do the eggs of Paragonimus westermani go through in the snail? a) One b) Two c) Three d) Four
Explanation: Inside the snail the parasite undergoes two redial generations before transforming into cercariae.
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64. What color are the characteristic eggs of Paragonimus westermani? a) Dark golden-brown b) Pale yellow c) White d) Red
Explanation: The eggs are dark golden-brown with a thick shell distinguishing them from other parasites.
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65. What size are the eggs of Paragonimus westermani? a) 80 to 120µm by 48 to 60µm b) 10 to 20µm by 5 to 10µm c) 50 to 100µm by 25 to 50µm d) 200 to 300µm by 100 to 150µm
Explanation: The eggs of P. westermani are large and elliptical measuring approximately 80–120µm by 48–60µm.
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66. Where are the eggs of Paragonimus westermani usually found? a) Urine b) Blood c) Sputum or feces d) All of the above
Explanation: Eggs are expelled from the host via sputum (from the lungs) or feces after being swallowed.
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67. What type of cells infiltrate the lungs in a Paragonimus westermani infection? a) Leukocytes b) Erythrocytes c) Thrombocytes d) Lymphocytes
Explanation: Leukocytes infiltrate the lungs due to the immune response against the parasite.
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68. What may result from inclusion of a Paragonimus westermani egg within the respiratory tree? a) Bronchiectasis b) Pneumonia c) Lung cancer d) Tuberculosis
Explanation: Eggs in the respiratory tract can lead to bronchiectasis due to chronic inflammation.
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69. Where are Paragonimus westermani worm cysts rarely seen? a) Lungs b) Peritoneal cavity c) Brain d) Liver
Explanation: Worm cysts are commonly found in the lungs and occasionally in the brain or liver but rarely in the peritoneal cavity.
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70. What is the treatment for Paragonimus westermani? a) Praziquantel b) Albendazole c) Metronidazole d) Ivermectin
Explanation: Praziquantel is the preferred treatment for Paragonimus infections.
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71. What is the dosage of praziquantel for treatment of pulmonary paragonimiasis? a) 10 mg/kg three times daily for 2 days b) 25 mg/kg three times daily for 2 days c) 50 mg/kg three times daily for 2 days d) 100 mg/kg three times daily for 2 days
Explanation: The recommended dose is 25 mg/kg three times daily for 2 days for optimal efficacy.
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72. What is an alternative drug for the treatment of pulmonary paragonimiasis? a) Albendazole b) Metronidazole c) Bithionol d) Ivermectin
Explanation: Bithionol is an alternative drug particularly when Praziquantel is unavailable.
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73. What is the dosage of bithionol for the treatment of pulmonary paragonimiasis? a) 10 to 15 mg/kg body weight once daily b) 15 to 25 mg/kg body weight twice daily c) 25 to 35 mg/kg body weight three times daily d) 35 to 45 mg/kg body weight four times daily
Explanation: The effective dose of bithionol is 15–25 mg/kg body weight administered twice daily.
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74. What other name is Fasciola hepatica known as? a) Lung fluke b) Liver fluke c) Blood fluke d) Intestinal fluke
Explanation: Fasciola hepatica is commonly referred to as the liver fluke because it infects the liver.
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75. What animal does Fasciola hepatica commonly attack? a) Pigs b) Goats c) Cattle and sheep d) Horses
Explanation: Fasciola hepatica primarily infects cattle and sheep causing significant economic loss in livestock.
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76. Where is Fasciola hepatica mostly found a) Asia b) North America c) Africa d) South America
Answer: c) Africa Explanation: Fasciola hepatica is commonly found in Africa particularly in areas with significant livestock farming where the parasite's life cycle can be sustained
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77. What is the shape of the anterior end of an adult Fasciola hepatica a) Round b) Square c) Triangular d) Cone-shaped
Answer: d) Cone-shaped Explanation: The anterior end of Fasciola hepatica is cone-shaped helping it attach to host tissues during parasitism
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78. Where are the oral sucker and testes located in Fasciola hepatica a) Posterior end b) Anterior end c) Middle of the body d) They are not present in Fasciola hepatica
Answer: b) Anterior end Explanation: The oral sucker and testes of Fasciola hepatica are located in the anterior region to facilitate feeding and reproduction within the host
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79. What is the function of the caeca in Fasciola hepatica a) Reproduction b) Excretion c) Digestion d) Respiration
Answer: c) Digestion Explanation: The caeca in Fasciola hepatica are part of its digestive system aiding in the absorption and processing of nutrients from the host
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80. Which diagnostic method is used to visualize the adult flukes in Fasciola hepatica infection a) X-ray b) Blood test c) Ultrasound d) Urine test
Answer: c) Ultrasound Explanation: Ultrasound imaging is used to detect adult flukes in the bile ducts or liver during Fasciola hepatica infection especially in cases of chronic fascioliasis
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81. What is the scientific classification of Trematoda
Answer: Trematoda belongs to the phylum Platyhelminthes class Trematoda Explanation: Trematoda is a class of parasitic flatworms that includes flukes characterized by a complex life cycle and parasitic stages in both vertebrate and invertebrate hosts
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82. Briefly describe the life cycle of a typical digenetic trematode
Answer: A typical digenetic trematode life cycle includes eggs miracidia sporocysts rediae cercariae and metacercariae with intermediate and definitive hostsExplanation: The life cycle of digenetic trematodes involves multiple developmental stages often requiring a snail as an intermediate host and a vertebrate as the definitive host
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83. What are the key morphological features of a digenetic trematode
Answer: Digenetic trematodes have a flattened leaf-shaped body with suckers a tegument and a bifurcated digestive tract Explanation: These features help trematodes attach to their host absorb nutrients and carry out their parasitic lifestyle effectively
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84. How are the eggs of different trematode species differentiated
Answer: Eggs are differentiated by their size shape operculum presence and surface textureExplanation: Trematode eggs have distinct characteristics that aid in species identification during microscopic examination
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85. Describe the differences between intestinal and liver trematodes
Answer: Intestinal trematodes inhabit the intestines while liver trematodes are found in the liver or bile ductsExplanation: These differences are based on the habitat within the host and the associated clinical manifestations such as abdominal pain for intestinal trematodes and jaundice for liver trematodes
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86. Explain the life cycle of schistosomes
Answer: Schistosome life cycle includes eggs miracidia sporocysts cercariae and adult worms with snails as intermediate hosts and humans as definitive hosts Explanation: Schistosomes exhibit a unique life cycle where cercariae penetrate human skin directly causing schistosomiasis
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87. What are the clinical symptoms of schistosomiasis
Answer: Symptoms include abdominal pain blood in urine or stool diarrhea and organ damageExplanation: Schistosomiasis results from immune responses to schistosome eggs trapped in tissues leading to inflammation and scarring
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88. How is schistosomiasis diagnosed and treated
Answer: Diagnosis involves stool or urine examination for eggs and treatment is with praziquantel Explanation: Microscopic detection of eggs confirms the infection while praziquantel effectively kills adult schistosomes
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89. Describe the pathology associated with Paragonimus westermani infection
Answer: Infection causes lung damage leading to chronic cough hemoptysis and chest pain Explanation: Paragonimus westermani migrates to the lungs causing inflammation and cyst formation leading to respiratory symptoms
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90. Explain the life cycle of Fasciola hepatica
Answer: The life cycle includes eggs miracidia sporocysts rediae cercariae metacercariae and adults with snails as intermediate hosts and ruminants or humans as definitive hosts Explanation: The parasite completes its development through water-dependent stages infecting hosts that consume contaminated vegetation or water
