MICROANATOMY

ENDOCRINE ORGANS AND RESPIRATORY SYSTEM

RESPIRATORY SYSTEM

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The large muscle that contracts and relaxes and moves air in and out of the lungs.
A
epiglottis
B
alveoli
C
diaphragm
D
trachea
Explanation: 

Detailed explanation-1: -The diaphragm, located below the lungs, is the major muscle of respiration. It is a large, dome-shaped muscle that contracts rhythmically and continually, and most of the time, involuntarily.

Detailed explanation-2: -Breathing in When you breathe in, or inhale, your diaphragm contracts and moves downward. This increases the space in your chest cavity, and your lungs expand into it. The muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale.

Detailed explanation-3: -The diaphragm is attached to the base of the sternum, the lower parts of the rib cage, and the spine. As the diaphragm contracts, it increases the length and diameter of the chest cavity and thus expands the lungs. The intercostal muscles and neck muscles help move the rib cage and thus assist in breathing.

Detailed explanation-4: -Expiration (exhalation) is the process of letting air out of the lungs during the breathing cycle. During expiration, the relaxation of the diaphragm and elastic recoil of tissue decreases the thoracic volume and increases the intraalveolar pressure. Expiration pushes air out of the lungs.

Detailed explanation-5: -Your diaphragm tightens and flattens, allowing you to suck air into your lungs. To breathe out (exhale), your diaphragm and rib cage muscles relax. This naturally lets the air out of your lungs.

There is 1 question to complete.