The heart is an organ that pumps blood throughout the circulatory system in the body. Red blood cells are a tissue in the body that carry nutrients to the body's cells and waste away from the body's cells. The heart rate increases or decreases depending on the body's needs to transport nutrients and waste.
In an experiment, a female had her heart monitored. For one minute, she sat in a chair quietly. At the end of the first minute to the end of the third minute she did jumping jacks. Finally, she sat again in the chair and waited until her heart rate went back to her resting heart rate as measured in the first minute. After performing this experiment, the following graph was created.
How long did it take for the resting heart rate to return after the exercising stopped?
- 1 minute 15 seconds
- 1 minute 30 seconds
- 1 minute 45 seconds
- 2 minutes
Answer(s): C
Explanation:
The exercise stopped at 4 minutes, but the heart rate did not return to its resting rate until about 5 minutes 45 seconds. Remember that between each of the minute lines on the graph, are 60 seconds. So, if a point falls halfway between 5 and 6 minutes, that is 5 minutes and 30 seconds.