just the structure of the tissue but also the physiological function and photo acoustics or optical imaging in general can provide that type of information in vivo metabolic imaging so this is someone like PET imaging positron emission tomography you know we're looking at metabolic parameters right so I enumerated a couple of examples such as the metabolic rate of oxygen glucose consumption rate we all know that these are the two major mechanisms of metabolism your body right in vivo molecular imaging so we're able