Respiratory System Trachea Basic Anatomy Of Lung

The figure shows a diagrammatic view of the human respiratory system with labels A, B, C, and D. Select the option that gives the correct identification, main function, and/or characteristics:

1.	B-pleural membrane- surrounds ribs on both sides to provide cushion against rubbing.
2.	C-alveoli-thin walled vascular bag-like structures for the exchange of gases.
3.	D-lower end of the lungs-diaphragm pulls it down during inspiration.
4.	A trachea-long tube supported by complete cartilaginous rings for conducting inspired air.

Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because?

1.	there is a negative pressure in the lungs
2.	there is a negative intrapleural pressure pulling at the lung walls
3.	there is a positive intrapleural pressure
4.	pressure in the lungs is higher than the atmospheric pressure

Which of the following is not the function of conducting part of respiratory system?

1.	Provides surface for diffusion of O2 and CO2
2.	It clears inhaled air from foreign particles
3.	Inhaled air is humidified
4.	Temperature of inhaled air is brought to body temperature