If its a heart its circulatory, lungs respiratory, kidneys excretory, brain nervous, stomach digestive, hormones endocrine, skin integumentary, lymph nodes lymphatic, bone skeletal, muscle muscular, thymus immune system.
But if you can show a pic i could try to answer it more specifically.
The answer is about 540-490 million years ago.
Answer:
At the gym work out gaining weight needs to adjust balanced.
The reactants of cellular respirationare oxygen and sugar, which are theproducts of photosynthesis. ... When plants are placed in darkness, cellular respiration continues, using ATP to convert sugar into ADP and releasing carbon dioxide. Photosynthesis stops in the absence of light energy.
