2 If the Daphnia heart rate experiment were performed on an endothermic organism what results would you expect?

If the Daphnia heart rate experiment were performed on an endothermic organism, we would expect to see different results compared to the experiment conducted on Daphnia, which is an ectothermic organism. Here are some key differences we might observe:

1. Higher Heart Rate: Endothermic organisms, such as mammals and birds, generally have higher metabolic rates and maintain a constant body temperature through internal heat production. This higher metabolic activity typically leads to a faster heart rate compared to ectothermic organisms. Therefore, we would expect the endothermic organism's heart rate to be higher than that of Daphnia, even under the same experimental conditions.

2. Less Variation in Heart Rate: Ectothermic organisms like Daphnia are highly influenced by external environmental factors such as temperature, which can significantly affect their heart rate. In contrast, endothermic organisms can regulate their body temperature and maintain relatively stable internal conditions. As a result, we would expect less variation in the heart rate of the endothermic organism throughout the experiment, despite changes in external temperature.

3. Different Temperature Response: In the Daphnia experiment, the heart rate typically increases with increasing temperature within a certain range. This relationship is often due to the effect of temperature on metabolic rate and enzyme activity. In endothermic organisms, however, changes in heart rate may not be as closely tied to temperature since they can maintain a constant internal temperature. Therefore, we might observe a different pattern of heart rate response to temperature in the endothermic organism.

4. Sustained Activity: Endothermic organisms can generate their own body heat, allowing them to sustain higher levels of activity compared to ectothermic organisms. In the experiment, this could mean that the endothermic organism might exhibit a more consistent heart rate over time, even during periods of increased activity or external temperature changes.

It's important to note that while these are general predictions based on the physiological differences between ectothermic and endothermic organisms, the actual results and patterns observed would depend on the specific endothermic organism used in the experiment. Additionally, factors such as the specific experimental conditions, the health and age of the organism, and variations between species within the endothermic group would also influence the observed outcomes.