They don't swell because of osmosis.
Answer:
Protein
Explanation:
This is because protein is a macronutrients and it is the building blocks which is important for building body mass and they are found through out the body, in the muscles, bones, skin, hair e.t.c
Protein can be gotten from both plants and animals.
The animal protein include meat, diary products, fishes e.t.c.
The plants protein include beans, r.t.c.
To have a definite shape and volume
The correct answer is mitochondria. Mitochondria is an organelle in the cell that corresponds to the function of the human lungs.It helps the lungs in the biochemical process of respiration and with the energy production (cellular respiration.)