Question

which belongs to each sentence?

In [external/ or cellular] respiration, these gases are exchanged between the body's tissues and the outside environment by way of the respiratory system. In [ external/ or cellular] respiration, these gases are used and created by the metabolic processes of the cells.

[alveolar capillary membranes, type 2 alveolar cells, type 1 alveolar cells] make up the main structure of the alveolar wall. The walls of the alveoli  are very thin, separated from the capillary vessels by an even thinner barrier called [alveolar capillary membranes, type 2 alveolar cells, type 1 alveolar cells] . [alveolar capillary membranes, type 2 alveolar cells, type 1 alveolar cells] occur on the inside surface of the alveoli and secrete liquids called pulmonary surfactants, to help the surface of the alveoli expand.

Which of the following is a general adaptation of the respiratory system that increases the rate of diffusion?

a. Decreasing the concentration gradient across the respiratory surface

b. Having a small respiratory surface area

c. Having a thin respiratory surface

Answer 1

In external respiration, these gases are exchanged between the body's tissues and the outside environment by way of the respiratory system. In cellular respiration, these gases are used and created by the metabolic processes of the cells.

Type 1 alveolar cells make up the main structure of the alveolar wall. The walls of the alveoli  are very thin, separated from the capillary vessels by an even thinner barrier called alveolar capillary membranes . Type 2 alveolar cells occur on the inside surface of the alveoli and secrete liquids called pulmonary surfactants, to help the surface of the alveoli expand.

Q. Answer - c. Having a thin respiratory surface

General adaptation of the respiratory system that increases the rate of diffusion are by

- increased surface area by alveolar shape

- Thin wall of respiratory surface - only one cell thick

- moist walls - helps diffusion