I am tempted to say that the nervous system processes the stimuli, or to be more specific, the neurons that go across our nervous system.
The metabolite called lactic acid causes the body, specifically the muscles to ache after performing exercises. During exercise, respiration takes place which converts glucose substituents to be converted into metabolites such as lactic acid.
Answer: The answer is true!
Explanation: The one cell of a unicellular organism must be able to perform all the functions necessary for life. These functions include metabolism, homeostasis and reproduction. Specifically, these single cells must transport materials, obtain and use energy, dispose of wastes, and continuously respond to their environment.