#1
Which structure separates the thoracic cavity from the abdominal cavity?
Diaphragm
ExplanationMuscular membrane essential for respiration, creating a barrier between chest and abdomen.
#2
Which of the following is not a component of the thoracic wall?
Scapula
ExplanationScapula, a bone of the shoulder girdle, is not part of the thoracic wall.
#3
Which structure forms the anterior boundary of the thoracic cavity?
Sternum
ExplanationBreastbone anchoring ribs, forming the front of the thoracic cage.
#4
Which chamber of the heart lies predominantly in the thoracic cavity?
Left ventricle
ExplanationThe left ventricle, responsible for pumping oxygenated blood to the body, is mainly located in the thoracic cavity.
#5
Which thoracic structure is responsible for the exchange of gases during respiration?
Alveoli
ExplanationTiny air sacs where gas exchange occurs, facilitating oxygen uptake and carbon dioxide release.
#6
Which muscle is primarily responsible for inspiration during quiet breathing?
Diaphragm
ExplanationContracts during inhalation, expanding the thoracic cavity and drawing air into the lungs.
#7
Which thoracic structure is responsible for the production of surfactant, aiding in lung function?
Alveoli
ExplanationAlveoli secrete surfactant, reducing surface tension and preventing lung collapse.
#8
The mediastinum contains all of the following structures except:
Lungs
ExplanationMediastinum holds vital structures like the heart, esophagus, and great vessels but not the lungs.
#9
Which artery supplies blood primarily to the thoracic wall?
Internal thoracic artery
ExplanationSupplies blood to the chest wall, breast, and diaphragm.
#10
Which structure passes through the esophageal hiatus of the diaphragm?
Esophagus
ExplanationEsophagus traverses the diaphragm, connecting the throat to the stomach.
#11
Which nerve innervates the diaphragm, a key muscle involved in respiration?
Phrenic nerve
ExplanationControls diaphragm movement, essential for breathing, receiving signals from the brain and spinal cord.