Sustained high fever (39° to 40°C), weakness, stomach pain, and constipation are common symptoms of:

[Human-Health-and-Disease] [class-xii ]

• Pneumonia
• Common cold
• Typhoid fever
• Ringworms
Correct Option: C  [ Typhoid fever ]

Remark: These symptoms are listed as common symptoms of typhoid fever.

The diagnostic test used to confirm typhoid fever is:

[Human-Health-and-Disease] [class-xii ]

• ELISA
• Widal test
• Biopsy
• MRI
Correct Option: B  [ Widal test ]

Remark: Typhoid fever could be confirmed by Widal test.

The pathogens responsible for pneumonia, such as Streptococcus pneumoniae and Haemophilus influenzae, infect the:

[Human-Health-and-Disease] [class-xii ]

• Large intestine
• Lymphatic vessels
• Alveoli of the lungs
• Respiratory passage but not the lungs
Correct Option: C  [ Alveoli of the lungs ]

Remark: These bacteria infect the alveoli (air filled sacs) of the lungs.

In severe cases of pneumonia, a visible symptom related to oxygen deprivation is:

[Human-Health-and-Disease] [class-xii ]

• The lips and finger nails may turn gray to bluish in colour
• Severe diarrhoea
• Formation of dry, scaly lesions
• Loss of appetite
Correct Option: A  [ The lips and finger nails may turn gray to bluish in colour ]

Remark: In severe cases of pneumonia, the lips and finger nails may turn gray to bluish in colour.

Common cold is caused by which group of viruses?

[Human-Health-and-Disease] [class-xii ]

• Retroviruses
• Oncogenic viruses
• Rhino viruses
• Herpes viruses
Correct Option: C  [ Rhino viruses ]

Remark: Rhino viruses cause one of the most infectious human ailments—the common cold.

Unlike pneumonia, the common cold viruses infect the nose and respiratory passage but explicitly do NOT infect the:

[Human-Health-and-Disease] [class-xii ]

• Pharynx
• Trachea
• Lungs
• Throat
Correct Option: C  [ Lungs ]

Remark: Rhino viruses infect the nose and respiratory passage but not the lungs.

Transmission of the common cold often occurs through contaminated objects such as:

[Human-Health-and-Disease] [class-xii ]

• Needles and syringes
• Doorknobs, pens, and computer keyboard or mouse
• Food contaminated by faecal matter
• Female *Anopheles* mosquito
Correct Option: B  [ Doorknobs, pens, and computer keyboard or mouse ]

Remark: The infection is transmitted through contaminated objects such as pens, books, cups, doorknobs, computer keyboard or mouse, etc..

The protozoan genus responsible for causing malaria is:

[Human-Health-and-Disease] [class-xii ]

• Entamoeba
• Ascaris
• Wuchereria
• Plasmodium
Correct Option: D  [ Plasmodium ]

Remark: Plasmodium, a tiny protozoan, is responsible for malaria.

Which species of Plasmodium causes malignant malaria, which is the most serious and potentially fatal type?

[Human-Health-and-Disease] [class-xii ]

• P. vivax
• P. malariae
• P. falciparum
• P. ovale
Correct Option: C  [ P. falciparum ]

Remark: Malignant malaria caused by Plasmodium falciparum is the most serious one and can even be fatal.

In the human body, Plasmodium enters as the infectious form known as:

[Human-Health-and-Disease] [class-xii ]

• Merozoites
• Gametocytes
• Sporozoites
• Trophozoites
Correct Option: C  [ Sporozoites ]

Remark: Plasmodium enters the human body as sporozoites (infectious form) through the bite of infected female Anopheles mosquito.