Respiratory Anatomy 3 - Thorax & Breathing

Question 1

This structure prevents the entry of food to the LRT and contains the vocal cord.

Answer 1

Larynx

Question 2

This carries air to the alveoli with changes to the epithelium, smooth muscle and cartilage reflecting function.

Answer 2

Bronchial tree

Question 3

Where does gas exchange occur specifically in the alveoli?

Answer 3

In the respiratory membrane

Question 4

What are the boundaries of the thorax? (anterior, posterior, lateral, superior and inferior)

Answer 4

Anterior: sternum
Posterior: thoracic vertebrae
Lateral: ribs
Superior: base of the neck (area between clavicle)
Inferior: diaphragm

Question 5

The thoracic cavity contains what 2 sections?

Answer 5

Mediastinum and pleural cavities

Question 6

This is where the bronchi enters the lung.

Answer 6

Hilum

Question 7

This is a section that contains the heart, vessels and pericardium.

Answer 7

Mediastinum

Question 8

Ventilation is driven by ________ _______ in the thoracic cavity.

Answer 8

Pressure changes (remember air moves down a pressure gradient)

Question 9

What is the state of the pressure inside cavity and pressure outside in between breaths?

Answer 9

Both pressures are equal so no movement of gas (because no pressure gradient)

Question 10

Increase in volume inside cavity (decrease in pressure) means the air will?

Answer 10

Move into the cavity (because cavity has lower pressure)

Question 11

Decrease in volume inside cavity (increase in pressure) means the air will?

Answer 11

Move out of the cavity (because the outside of the cavity has lower pressure)

Question 12

How do we change the volume of the thorax?

Answer 12

Through joints

Question 13

What are the nature of the joints in the anterior boundary of the thoracic cavity?

Answer 13

Anterior boundary (sternum and ribs)

• synovial joints (hyaline cartilage, but because it’s in the ribs = costal cartilage)
• cartilaginous joints (fibrocartilage)

Question 14

Sternocostal joints are what type of joints?

Answer 14

Synovial (except for the 1st one, because the first one is anchored to the sternum for stability in the base of the neck)

Question 15

Why are synovial joints significant in breathing?

Answer 15

Synovial joints allow a lot of movement, so they enable us to breathe in and out. (to allow for that lifting up of the thoracic cage)

Question 16

Costochondral joints are what type of joints?

Answer 16

Cartilaginous joints

Question 17

Interchondral joints are what type of joints?

Answer 17

Synovial joints

Question 18

This is the joint between the rib and transverse process of the vertebrae.

Answer 18

Costotransverse

Question 19

This is the joint between the rib and body of the vertebrae.

Answer 19

Costovertebral

Question 20

Joints allow movement to occur, but what creates the movement?

Answer 20

Muscles

Question 21

What are the 2 primary muscles of respiration?

Answer 21

Diaphragm and intercostals (muscles in between the ribs)

Question 22

This is a sheet of skeletal muscle that separates thorax from abdomen. Its contraction expands thoracic cavity and compresses abdominopelvic cavity

Answer 22

Diaphragm

Question 23

These muscles attach diagonally between neighbouring ribs.

Answer 23

Intercostal muscles

Question 24

These are the muscles that lift ribcage and expand cavity. The nature of inspiration is quiet and forced.

Answer 24

External intercostals

Question 25

These are the muscles that depress the ribcage and decrease the size of the cavity. Expiration is forced only.

Answer 25

Internal intercostals.

Question 26

These muscles contract to further expand the thoracic cavity,

Answer 26

Accessory muscles

Question 27

Lungs expand during?

Answer 27

Inspiration

Question 28

Lungs contract during?

Answer 28

Expiration