Second Part: Finals questions ll Flashcards
What is the central tendon of the diaphragm?
a tough sheet of inelastic tissue
Describe the 4 steps of the diaphragm in action:
- Thoracic volume increases.
- Intrapulmonic pressure decreases.
- Abdominal volume decreases.
- Intraabdominal pressure increase
What are intercostal muscles?
Muscles that are in between ribs
What do the internal intercostals do?
They make the ribs go DOWN AND IN during forced exhale. They decrease the total volume in the cavity & increase pressure
What do the external intercostals do during forced inhalation?
They elevate the ribs during forced inhalation and increase the total volume of the thoracic cavity. MAKES THE RIBS GO UP AND OUT.
What does the transversus thoracic muscle do?
Depresses ribs
Where is the transversus thoracic muscle located?
What are costal elevators?
- Rib raisers
- (levatores costarum) vertibrae (C7-T11)
What is the pectoralis major? (3)
- A thick, fan-shaped muscle situated on the anterior chest wall. It makes up the bulk of the chest muscles.
- Connects to humerus, sternum, clavicle and upper costal
- pulls sternum and ribs up when humerus is fixed
What is the pectoralis minor? (2)
- Muscle attached to scapula, and deeper than the pectoralis major
- elevates ribs when scapula is fixed
What is the subclavius?
- Muscle that connects clavicle to the first rib
- Elevates first rib when clavicle is fixed
What is the serratus anterior?
- Muscle that attaches the upper ribs to the scapula (shoulder blades)
- Upper ribs elevate when scapula is fixed
What is the sternocleidomastoid? (2)
- Muscle that attaches sternum & clavicle to the mastoid (temporal bone)
- When head held is fixed, bilateral contraction elevates sternum and clavicle
What are the scalene muscles? (2)
- anterior, middle, posterior
- deep muscles of anterolateral region of the neck
What are the anterolateral abdominal muscles?
- They compress abdominal contents resulting in forced expiration
What are the external obliques?
- Muscle that connects the lower ribs to the abdominal aponeurosis
- Largest, strongest, most superficial
What are the internal obliques?
- Deep muscles that course opposite to external obliques
- same role as external obliques
What are subcostal muscles?
- Inside the back wall of the ribs
- lower ribs
Breathing in is ___________, breathing out is _____________. (active or passive)
Breathing in is active, breathing out is passive.
Describe what occurs during active inhalation. (4)
- Diaphragm and intercostals ?
- lungs ?
- abdominal viscera?
- inspiratory muscles?
- Diaphragm and intercostals contract
- lungs expand with thoracic enlargement
- abdominal viscera is compressed by the diaphragm
- inspiratory muscles cease contraction