CBSE 2023 · Region 3 · Set 1 · Q30 · 4 marks
The diagram shows the life cycle of a pathogenic protozoan.
(i)Name the parasitic stage that is being transferred from host 'X' to host 'Y'.(ii)Write the changes the parasite undergoes in the liver.(iii)Write the changes the parasite undergoes when it enters the RBC.(iv)Trace the changes the parasite undergoes when the host 'X' takes its blood meal from infected host 'Y'.At which stage during the life cycle of the pathogen does the host 'Y' experience the symptoms of the disease ? Name the disease and the toxic substance responsible for these symptoms.
The diagram shows the life cycle of a pathogenic protozoan.
(i)
Name the parasitic stage that is being transferred from host 'X' to host 'Y'.
(ii)
Write the changes the parasite undergoes in the liver.
(iii)
Write the changes the parasite undergoes when it enters the RBC.
(iv)
Trace the changes the parasite undergoes when the host 'X' takes its blood meal from infected host 'Y'.
At which stage during the life cycle of the pathogen does the host 'Y' experience the symptoms of the disease ? Name the disease and the toxic substance responsible for these symptoms.
Marking-scheme solution
(i)
Sporozoites.
(ii)
Undergoes Asexual reproduction
(iii)
The number increase asexually, parasites ultimately change into gametocytes/ undergoes gametogenesis
(iv)
Fertilisation and development_takes place in host 'X', ultimately forming the infective stage sporozoites.
Bursting of RBCs
Malaria
Haemozoin
Human Health and DiseaseAIDSUnderstandcase_studymedium
More from Human Health and Disease
- Name the category of drugs represented by the chemical structure given above. If the methyl group is…2023 · asked 3×
- Lactobacillus that sets milk into curd is categorised as:2024 · asked 3×
- Explain, giving two reasons, how immune response by "vaccine" is different from that by "antitoxin" in humans.2022 · asked 3×
- Student to attempt either option or. Describe any two situations where a medical doctor would recommend…2025 · asked 3×
- (i) Draw the structure of an antibody molecule and label any four of its parts. (ii) Differentiate between…2026 · asked 3×
- Assertion: Virus-infected cells produce interferons. Reason (R): Interferons can cause inflammation of…2024 · asked 3×
- Out of the following, select the correct match:2025 · asked 3×
- Though filariasis is not fatal, but the disease in humans is responsible for considerable suffering, gross…2022 · asked 3×
CBSE Class 12 Biology past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.