Tag: gas exchange and smoking

Questions Related to gas exchange and smoking

One of the following is a difference between pulmonary respiration of frog and human.

  1. Diaphragm and ribs play role in respiration

  2. Lungs are respiratory organs

  3. Respiration occurs due to pressure gradient

  4. None of the above


Correct Option: A

Lungs have a large number of narrow tubes called.

  1. Alveoli

  2. Bronchioles

  3. Bronchi

  4. Alveolar ducts


Correct Option: B
Explanation:

From the larynx, air moves into lower respiratory tract, starting with the trachea and down to the intersection that branches to form the right and left primary (main) bronchi. Each of these bronchi branch into secondary (lobar) bronchi that branch into tertiary (segmental) bronchi that branch into smaller narrow tube airways called bronchioles that eventually connect with tiny specialized structures called alveoli that function in gas exchange.

So, the correct option is 'Bronchioles'.

In mammals ventilation movements of lungs are governed by.

  1. Muscular wall of lungs

  2. Intercostal muscles

  3. Diaphragm

  4. Diaphragm and intercostal muscles.


Correct Option: D

Number of alveoli in the two human lungs is?

  1. $600-800$ million

  2. $200-300$ million

  3. $1-2$ million

  4. $100,000-150,000$


Correct Option: A
Explanation:
Alveoli are the basic unit of ventilation. The number of alveoli is a key structural determinant of lung architecture. Alveolar number is closely related to total lung volume, with larger lungs having considerably more alveoli, ranging from 600-800 million. 
So, the correct option is '600-800 million'.

Lungs have a large number of alveoli for.

  1. Having spongy texture and proper shape

  2. More surface area for diffusion of gases

  3. More space for increasing volume of inspired air

  4. More nerve suply


Correct Option: B

Air is breathed through.

  1. Trachea $\rightarrow$ lungs $\rightarrow$ larynx $\rightarrow$ pharynx $\rightarrow$ alveoli

  2. Nose $\rightarrow$ larynx $\rightarrow$ pharynx $\rightarrow$ bronchus $\rightarrow$ alveoli $\rightarrow$ bronchioles

  3. Nostrils $\rightarrow$ pharynx $\rightarrow$ larynx $\rightarrow$ trachea $\rightarrow$ bronchi $\rightarrow$ bronchioles $\rightarrow$ alveoli

  4. Nose $\rightarrow$ mouth $\rightarrow$ lungs


Correct Option: C

Presence of large number of alveoli around alveolar ducts opening into bronchioles in mammalian lungs is?

  1. Inefficient system of ventilation with little of residual air

  2. Inefficient system of ventilation with high percentage of residual air

  3. An efficient system of ventilation with no residual air

  4. An efficient system of ventilation with little residuak air


Correct Option: D

Residual air mostly occurs in.

  1. Alveoli

  2. Bronchus

  3. Nostrils

  4. Trachea


Correct Option: A

Trachea is lined with incomplete rings of

  1. Fibrous cartilage

  2. Calcified cartilage

  3. Elastic cartilage

  4. Hyaline cartilage


Correct Option: D
Explanation:
The trachea is also called as windpipe. It is a cartilaginous tube which connects pharynx and larynx to the lungs, allowing passage of air. The wall of the trachea is lined by C shaped incomplete cartilaginous rings to protect it from collapsing during the breathing process due to pressure exerted on its walls by the air. These incomplete rings are made up of hyaline cartilage.
So, the correct answer is 'Hyaline cartilage'.

Gases diffuse over the respiratory surface because of.

  1. $pO _2$ is more in alveoli than in blood

  2. $pO _2$ is more in blood than in tissues

  3. $pCO _2$ is more in alveoli than in blood

  4. $pCO _2$ is more in blood than in tissues


Correct Option: A