Does the respiratory system have smooth muscles that surrounds the bronchioles?

Answer 1

It has smooth muscles in order to support the lungs

It is the role of cartilage to structurally support the trachea so it does not collapse in on itself (pulmonary atelectasis) during inspiration when the pressure in the lungs drops below atmospheric level.

No that is wrong, smooth muscle is controlled subconsciously by the autonomic nervous system, and its function is to constrict or dilate, (by contracting or relaxing respectively), the airways to ease or restrict air flow through them. For example when you exercise, the smooth muscle will relax causing the diameter of the trachea to increase so more air can flow through them and hence allow a greater volume of oxygen to processed as needed by the body for respiration to release energy and provide this to the muscle cells during exercise. However, when one is surrounded by something which one is toxic such as a harmful gas, then the smooth muscle may contract and constrict the airways to reduce airflow and thus the amount of this toxic substance from entering the lungs and damaging the lung tissue.

Answer 2

Yes, smooth muscle is found around the bronchi. It can relax or contract. It does this so that the airways can constrict, decreasing the diameter of the airways. Smooth muscle is also found surrounding the trachea and the bronchioles.

Answer 3

Bronchi

- large diameter

- cartilaginous

- higher resistance to airflow (than bronchioles)

Bronchioles

- smaller diameter

- smooth muscle cells

- lower resistance to airflow (due to many bronchioles in series)

- fewer goblet cells

Answer 4

No, the Primary Bronchi has more cartilage than the Secondary. As the bronchi continues its path from the Primary to it's end point the amount of cartilage decreases and smooth muscle increases, until eventually there is no cartilage present.

Answer 5

Yes, there is smooth muscle in bronchi.