Previous year MCQs

General science UPPSC 2021 GS-I
Question

Site of gaseous exchange in lungs is:

Answer & Solution

Answer: (Detailed Solution Below)

Option D: Alveoli

Detailed Solution:

The correct answer is “Alveoli”.
The alveoli are the key structures in the lungs where the exchange of gases—oxygen and carbon dioxide—occurs during the breathing process.

Similar Questions:

Brain diseases are diagnosed by
  1. A) ECG
  2. B) EEG
  3. C) EMG
  4. D) EKG
Which one of the following is not correctly matched?
Vitamin - Role
  1. A) Vitamin B12 - Antianaemic factor
  2. B) Vitamin C - Antiscorbutic factor
  3. C) Vitamin D - Antisterility factor
  4. D) Vitamin K - Antihaemorrhagic factor
The mirror used by a dentist to examine the teeth of patients is
  1. A) Concave
  2. B) Convex
  3. C) Plane
  4. D) Cylinderical
Which one of the following is used in food preservation?
  1. A) Sodium Carbonate
  2. B) Acetylene
  3. C) Benzoic Acid
  4. D) Sodium Chloride
Which one of the following minerals is necessary to control heart beat?
  1. A) Sodium
  2. B) Sulphur
  3. C) Potassium
  4. D) Iron
Which one of the following is a bio-diesel plant?
  1. A) Java grass
  2. B) Jatropa
  3. C) Guggul
  4. D) Rosha grass
The energy of the sun is produced by?
  1. A) Ionisation
  2. B) Nuclear fusion
  3. C) Nuclear fission
  4. D) Oxidation
What is the function of a pace maker?
  1. A) It regulates the heart beat
  2. B) It increases the heart beat
  3. C) It accelerates blood supply to heart
  4. D) It decreases the heart beat
Botulism is:
  1. A) Food borne infection
  2. B) Food-borne intoxication
  3. C) Water-borne infection
  4. D) Water-borne intoxication
Consider the following events and arrange them into chronological order:

1. Sharda Act
2. Nehru Report
3. Simon commission
4. Dandi march

Select the correct answer using the codes given below:
  1. A) 3, 2, 1, and 4
  2. B) 1, 2, 3 and 4
  3. C) 4, 3, 2 and 1
  4. D) 1, 4, 2 and 3
Average blood pressure of human being is:
  1. A) 60/100
  2. B) 20/80
  3. C) 60/140
  4. D) 120/80
Red light is used for danger signals because it:
  1. A) is scattered least
  2. B) is soothing to eye
  3. C) has least chemical effect
  4. D) is absorbed least by air