In class 10 biology, a heartbeat refers to the rhythmic contraction and relaxation of the heart muscles, occurring continuously from birth until death.
This process allows the heart to pump blood throughout the body, delivering oxygen and nutrients to cells and removing waste products. The heart's rhythmic actions are what we perceive as a heartbeat.
Here's a more detailed explanation:
- Contraction (Systole): The heart muscles squeeze, pushing blood into the arteries.
- Relaxation (Diastole): The heart muscles relax, allowing the heart to fill with blood.
The number of heartbeats per minute is called the heart rate. A healthy adult typically has a resting heart rate of around 70 to 80 beats per minute, although this can vary depending on factors such as age, fitness level, and overall health. This rate can fluctuate based on various factors:
- Exercise: During physical activity, the heart rate increases to meet the body's demand for oxygen.
- Stress: Stress hormones can also elevate the heart rate.
- Sleep: The heart rate generally decreases during sleep.
Understanding the heartbeat is crucial for comprehending the circulatory system and its role in maintaining life.
