Final answer:
It is true that higher temperatures can lead to a decrease in muscle tone and urine volume as the body conserves water and prioritizes cooling.
Step-by-step explanation:
The statement that at higher temperatures, the human body tends to experience a decrease in muscle tone and urine volume is true. During conditions of increased temperature, such as on a hot day or during exercise, the body attempts to cool down and maintain a balanced internal environment. Sweating is one of the primary methods used to dissipate excess heat.
Consequently, there is a decrease in the amount of water in the body, leading to decreased urine volume, because the kidneys work to conserve water. Additionally, muscle tone may decrease as the body prioritizes sending blood to the skin for cooling over muscle contraction.