Biology

Respiration and Gas Exchange

958 Questions

Access a targeted set of questions on respiration and gas exchange for competitive exams. Topics include lung volumes, the mechanism of breathing, and respiratory anatomy. Understanding these physiological processes is essential for scoring well.

Lung volumes and capacitiesBreathing mechanismsRespiratory anatomyGas exchange processes

Respiration and Gas Exchange Questions

Multiple choice zoology gas exchange and smoking gas exchange gas exchange in humans respiratory system in humans

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
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The large number of alveoli maximizes the surface area available for the diffusion of oxygen and carbon dioxide, which is essential for efficient respiration.

Multiple choice zoology gas exchange in humans gas exchange and smoking gas exchange respiratory system in humans

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
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Air follows the pathway: Nostrils -> Pharynx -> Larynx -> Trachea -> Bronchi -> Bronchioles -> Alveoli.

Multiple choice zoology gas exchange and smoking gas exchange gas exchange in humans respiratory system in humans

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
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The presence of alveoli allows for efficient gas exchange. Residual air (the air remaining in lungs after forced expiration) is a normal feature of mammalian lungs that prevents collapse.

Multiple choice zoology gas exchange and smoking gas exchange gas exchange in humans respiratory system in humans

Surfactant is?

  1. Protein produced by type II alveolar cells

  2. Excessive in many premature infants causing difficulty in breathing

  3. Decreases surface tension of fluid lining alveoli

  4. Lacking in individuals suffering from acute respiratory distress syndromes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Pulmonary surfactant is a mixture of lipids and proteins that reduces the surface tension of the fluid lining the alveoli, preventing them from collapsing during expiration.

Multiple choice zoology gas exchange and smoking gas exchange gas exchange in humans respiratory system in humans

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 in higher than the atmospheric pressure
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice zoology gas exchange and smoking gas exchange gas exchange in humans respiratory system in humans

During respiration, exchange of gases take place in

  1. Trachea and larynx

  2. Alveoli of lungs

  3. Alveoli and throat

  4. Throat and larynx
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Alveoli are the air sacs of the lungs. They have thin walls surrounded by blood capillaries (another layer of simple squamous epithelium). Gas exchange occurs in the alveoli. During inhalation, oxygen gas is in higher concentration in the alveoli than in the blood and so it diffuses into the blood through this thin layer of cells. During exhalation, carbon dioxide is in higher concentration in the blood than in the alveoli and so it diffuses into the alveoli through this thin layer of cells.

So, the correct answer is option B.

Multiple choice zoology gas exchange and smoking gas exchange gas exchange in humans respiratory system in humans

Choose the correct answer from the alternatives given.
What are the two large branches of the airway which lead off the trachea at the tracheal bifurcation?

  1. Alveoli

  2. Bronchi

  3. Metavenules

  4. Bronchioles
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The two large branches of the airway that lead off the trachea at the tracheal bifurcation are the bronchi. They act as the main passageway into the lungs. Each bronchus enters one of the two (either the left or the right lung). Within the lungs, the bronchi branch off into smaller and smaller passageways, the smallest of which are called bronchioles and at the end of the bronchioles are tiny air sacs that are known as the alveoli. The re-oxygenized blood is sent through meta venules to the pulmonary vein. So, the correct option is 'bronchi'.