Coronary Blood Flow Mechanisms

The video discusses the control of coronary blood flow, focusing on two main mechanisms: local factors and nervous control. It explains the normal coronary blood flow rate and how it changes during exercise or other conditions. Local factors include the decrease in oxygen leading to vasodilator formation, while nervous control involves sympathetic and parasympathetic innervation affecting heart rate and blood vessel dilation.

What is the normal rate of coronary blood flow to the heart?

• 225 ml per minute

• 425 ml per minute

• 125 ml per minute

• 325 ml per minute

Which arteries are primarily responsible for supplying blood to the heart?

• Carotid and Subclavian Arteries

• Aorta and Pulmonary Artery

• Right and Left Coronary Arteries

• Femoral and Brachial Arteries

During which phase does coronary blood flow decrease?

• Diastole

• Systole

• Both Diastole and Systole

• Neither Diastole nor Systole

What is the primary local factor that increases coronary blood flow?

• Increase in carbon dioxide

• Decrease in oxygen

• Decrease in heart rate

• Increase in blood pressure

Which substance is a key vasodilator formed due to decreased oxygen levels?

• Nitric oxide

• Sodium ions

• Adenosine

• Calcium ions

Which of the following is NOT a vasodilator involved in coronary blood flow?

• Hydrogen ions

• Carbon dioxide

• Potassium ions

• Calcium ions

What role does the sympathetic nervous system play in coronary blood flow?

• Increases vasodilation

• Decreases blood flow

• Increases blood vessel constriction

• Decreases heart rate

How does the parasympathetic nervous system affect coronary blood flow?

• Increases blood flow

• Increases heart rate

• Decreases blood flow

• Has no effect

What happens to coronary blood flow when the heart's metabolic needs increase?

• It fluctuates randomly

• It increases

• It remains the same

• It decreases

Which system is responsible for the 'fight or flight' response affecting coronary blood flow?

• Parasympathetic system

• Sympathetic system

• Central nervous system

• Peripheral nervous system