Final answer:
Option (A), The heart rate does not increase when pressure is applied to the carotid artery. Instead, a reflex can slow the heart rate and decrease blood pressure.
Step-by-step explanation:
The heart rate does not typically increase when you push on the carotid artery. In fact, massaging the carotid sinus, located at the base of the carotid artery, can induce a reflex that decreases heart rate and blood pressure because it is perceived by the body as an increase in blood pressure.
This is because the baroreceptors in the carotid sinus are sensitive to pressure changes.
Regarding the other questions:
- When the heart rate increases above 160 bpm in a healthy young adult, cardiac output may actually start to decrease because there is less time for the heart to fill between beats.
- The coronary arteries indeed carry oxygenated blood to the heart muscle itself, which is essential for its function.
- Systole is the phase of the heartbeat when the heart muscle contracts and pumps blood out, while diastole is when the heart muscle is relaxed and the chambers fill with blood.
- Blood from the cardiac veins empties into the right atrium of the heart for recirculation to the lungs for oxygenation.
- The heart is primarily composed of cardiac muscle tissue, not smooth muscle.
- Sprinting is considered an anaerobic exercise because it involves short bursts of high-intensity activity where the demand for oxygen exceeds the supply.
- It is false that blood in the pulmonary veins is deoxygenated; it is actually reoxygenated after passing through the lungs.
- A pebble dropped in water does generate ripples, which are analogous to a pulse wave in the context of fluid dynamics, even though the mechanics differ.