Water
calcium
I think that it is water but I can't be sure. We just learned this in science so I might know. If I find out I will post it.
True. Fat is the nutrient with the highest concentration of energy, providing approximately 9 calories per gram, compared to carbohydrates and proteins, which each provide about 4 calories per gram. This high energy density makes fat an important source of fuel for the body, especially during prolonged physical activity.
The lungs of course
The highest concentration of mitochondria in the human body is found in muscle cells, particularly in the muscles used for endurance activities like the heart and skeletal muscles.
The highest carbon dioxide concentration in the body will be found in the tissues and cells, where it is produced as a byproduct of cellular metabolism. This carbon dioxide is then transported via the bloodstream to the lungs for exhalation.
Infants have the highest protein needs relative to body weight of any time of life.
the dead sea is the saltiest body of water in the world.
The highest concentration is in atmosphere. It is not on crust.
The blood in the pulmonary veins contains the highest concentration of oxygen since it has just been oxygenated in the lungs before returning to the heart to be pumped to the rest of the body.
The highest concentration of solutes in tubular fluid is found in the deep medullary regions of the kidney, known as the renal medulla. This high solute concentration is necessary for the kidneys to concentrate urine and maintain water balance in the body.
Muscle cells have the highest concentration of mitochondria.