Veterinary Anatomy I: exam 2 Cardiorespiratory 2. Continuation

Flashcards covering key anatomical structures and functions related to the cardiorespiratory system, including the diaphragm, thoracic cavity, heart chambers, valves, coronary vessels, and heart sounds from Veterinary Anatomy I lecture notes.

What is the primary function of the diaphragm in respiration?

It functions in respiration by aiding in the expansion and contraction of the thoracic cavity.

Which structures define the limits of the thoracic cavity?

The limits include the thoracic inlet, the thoracic wall, and the diaphragm caudally.

What are the four main subdivisions within the thorax?

The thoracic cavity, mediastinum, pleural cavities, and pericardial cavity.

What is the role of the pleura and pericardium?

They are mesothelial and connective tissue structures that define the pleural and pericardial cavities, offering protection and reducing friction.

Where is the normal orientation of the heart within the thoracic cavity for dogs and cats?

The heart is normally oriented with its long axis tilted slightly to the left and ventrally.

Which major vessels enter the right atrium?

The cranial vena cava, caudal vena cava, and azygos vein.

What are the muscular ridges found on the internal walls of the ventricles?

Trabeculae carneae.

What is the function of the chordae tendineae in the heart valves?

They are fibromuscular cords that attach the valve cusps to the papillary muscles, preventing valve prolapse during ventricular contraction.

What is the 'lub' sound of the cardiac cycle attributed to?

The closure of the atrioventricular (tricuspid and mitral) valves at the beginning of systole.

What is the 'dub' sound of the cardiac cycle attributed to?

The closure of the semilunar (aortic and pulmonary) valves at the beginning of diastole.

Where is the pulmonary valve heard best during auscultation?

On the left side, typically in the 3rd intercostal space.

Where is the aortic valve heard best during auscultation?

On the left side, typically in the 4th intercostal space.

Where is the mitral (left atrioventricular) valve heard best during auscultation?

On the left side, typically in the 5th intercostal space.

Where is the tricuspid (right atrioventricular) valve heard best during auscultation?

On the right side, typically in the 4th intercostal space.

What is the origin and function of the coronary arteries?

They originate from the aorta and branch off to supply oxygen-rich blood to the entire heart muscle.

Which major branches arise from the left coronary artery?

The paraconal interventricular branch, circumflex branch, septal branch, subsinuosal interventricular branch, and intermedial branch.

Which venous structure collects most of the deoxygenated blood from the heart muscle and drains into the right atrium?

The coronary sinus, which receives blood from veins like the great cardiac vein and middle cardiac vein.