If you are adding something to the water the concentration of water would drop, as it would start off as 100% water but then with the addition of another substance it would change that from 100% free to x% free, due to the water dissolving the substance.
Muscle contraction happens only when the energy molecule called adenosine triphosphate (ATP) is present
The functions of eyes parts are as follows:
Retina: The rays of light focused on the retina by the cornea and lens. The retina produces an image which is sent along the optic nerve of the brain.
Iris: It changes the size of pupil and allows different amount of life to enter the eyes.
Pupil: The light enters to the eyes through it.
Cornea: It forms the outer coating of the eyeball and covers the iris and pupil.
Lens:
The pituitary gland secretes follicle stimulating hormone, which acts on the follicles and stimulates them to produce progesterone.
