Question
The diagram shows the breathing system in humans. Which labelled part is surrounded by blood capillaries for gas exchange?
▶️Answer/Explanation
Ans D
The correct answer is D, because :
In labelled diagram, parts are :
• A – Trachea (helps in passage of air to lungs)
• B – Bronchi (passage of air to lungs)
• C – Bronchioles ( passages air to the alveoli)
• D – Alveoli ( helps in gaseous exchange, which are surrounded by blood capillaries)
Question
Which process do living organisms use to remove excess carbon dioxide from their bodies?
A excretion
B movement
C nutrition
D respiration
▶️Answer/Explanation
Ans A
The correct answer is D, because :
• Respiration is the process of removing excess carbon dioxide from their bodies
• Excretion is removal of waste substances from body
• Nutrition is the intake of nutrient containing foods
• Respiration is the production of energy from food substances absorbed
Question
Which structure in the breathing system has the thinnest wall?
A alveolus
B bronchiole
C bronchus
D trachea
▶️Answer/Explanation
Ans A
The correct answer is A, because :
In gaseous exchange system, the gaseous exchange occurs at site of alveoli which will be having thinnest wall as it’s through diffusion.
Whereas,
• Bronchiole is thin but not at as alveoli.
• Bronchus and trachea are not thin
Question
Which table correctly shows the difference in composition of inspired air compared with expired air?
▶️Answer/Explanation
C
The correct answer is C, because :
In inspiration, air intake is from air space to lungs which contains high oxygen concentration and low carbon dioxide concentration.
So, correct is option C