D) On Sunday, Julia ran for three miles, causing a greater than average amount of perspiration and exhalation of water vapor.
The answer is: 'constrict the blood vessels in their large ears to reduce transfer of external heat to the blood in their ears.' This is an example of thermoregulation. Thermoregulation is the ability of the<span> </span>body to keep body temperature<span> within certain boundaries, even when the temperature of the surrounding environment is very different. The regulation of temperature by thermoregulating organisms is one aspect of </span>homeostasis. By using heat exchange systems, such as employed in this example, the animal will need to expend less energy on behavioural adaptations to maintain a constant body temperature.
An exposure to sarin or sarin like chemical will caused the sarcoplasmic reticulum to be continuously stimulated by the continual electrical signal. This will open the calcium channels and allows the calcium ions to bind continuously with troponin. Sarin is an organophosphorus chemical which is highly poisonous. It is used as a chemical weapon of destruction.
The ability of an animal to maintain a stable internal environment is called homeostasis