Answer:
I would assume D
Explanation:
Tube 1 doesn't contain an organism so it can't be that one. Both a snail and a plant are considered an organism, and cellular respiration occurs in almost any organism's cells
The definition of calories is a measure of energy in food, specifically the measure of heat needed to raise a kilogram or a gram of water by one degree Celsius.
The correct answer is (a.) Its spindle-shaped cells allow it to do smooth muscles. The structure of the cardiac muscles which is spindle-shaped is very important for the heart to withstand the stretching of the muscles during the contractions. Also for its smooth surface which is very important to prevent any possible blood clot during circulation.