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"Q: What type of muscle is cardiac muscle?"

"A: Involuntary muscle."

"Q: What is the general structure of the heart?"

"A: It is a hollow

"Q: Where is the heart located?"

"A: It rests on the diaphragm

"Q: What is the mediastinum?"

"A: The central compartment of the thoracic cavity that contains the heart

"Q: Where is the apex of the heart located?"

"A: At the 5th intercostal space

"Q: What is the function of the heart?"

"A: To pump blood

"Q: Describe the basic blood flow through the heart and body."

"A: Blood from the body enters the right atrium via the vena cava

"Q: What cavity is the heart located in?"

"A: The ventral cavity → thoracic cavity → mediastinal cavity."

"Q: What are the two main circuits of blood flow in the body?"

"A: Pulmonary circuit: between the heart and lungs; Systemic circuit: between the heart and the rest of the body."

"Q: Trace the pathway of blood through the heart and lungs."

"A: Body → Right atrium → Right ventricle → Lungs (for oxygen) → Left atrium → Left ventricle → Aorta → Body"

"Q: Which artery is unique for carrying deoxygenated blood?"

"A: The pulmonary artery (it carries blood from the heart to the lungs to get oxygen)."

"Q: What is the pericardium?"

"A: A double-layered sac that surrounds and protects the heart."

"Q: What are the two layers of the pericardium?"

"A: Visceral layer (epicardium) — directly on the heart surface; Parietal layer — outer layer attached to surrounding structures."

"Q: What is found between the visceral and parietal pericardial layers?"

"A: The pericardial (potential) space

"Q: What happens if there is too much fluid in the pericardial space?"

"A: It can compress the heart and impair its ability to pump (cardiac tamponade)."

"Q: What are the three layers of the heart wall?"

"A: 1. Epicardium — outer layer (visceral pericardium)\n2. Myocardium — middle muscular layer responsible for pumping\n3. Endocardium — inner lining continuous with blood vessel lining"

"Q: How many chambers does the heart have

and what are they?"

"Q: Why do atria have thinner walls than ventricles?"

"A: Because they only need to pump blood a short distance (to the ventricles)."

"Q: What separates the left and right ventricles?"

"A: The interventricular septum."

"Q: Which ventricle has a thicker wall

and why?"

"Q: Which ventricle has a thinner wall

and why?"

"Q: What is the function of the coronary sinus?"

"A: It is a large vein on the back of the heart that collects deoxygenated blood from the cardiac veins and drains it into the right atrium."

"Q: What is the tricuspid valve and where is it located?"

"A: The AV valve between the right atrium and right ventricle; it has three leaflets."

"Q: What structures hold the AV valve leaflets in place?"

"A: Chordae tendineae attached to papillary muscles in the ventricle wall."

"Q: What is the function of papillary muscles during heart contraction?"

"A: They tighten the chordae tendineae to prevent valve prolapse when the ventricles contract."

"Q: What valve does blood pass through as it leaves the right ventricle?"

"A: The pulmonary semilunar valve

"Q: How does blood return from the lungs to the heart?"

"A: Through the pulmonary veins into the left atrium."

"Q: What is the AV valve on the left side of the heart called?"

"A: The bicuspid valve

"Q: What valve does blood pass through as it leaves the left ventricle?"

"A: The aortic semilunar valve

"Q: What is the complete path of blood through the heart and lungs?"

"A: Right atrium → Tricuspid valve → Right ventricle → Pulmonary semilunar valve → Pulmonary arteries → Lungs → Pulmonary veins → Left atrium → Bicuspid (mitral) valve → Left ventricle → Aortic semilunar valve → Aorta → Body"