Wave
A wave is a rhythmic movement that carries energy through matter or space.
Waves.
That could be electromagnetic waves, or gravitational waves.
Photosynthesis is powered by light energy from the sun; and sunlight is a type of energy called electromagnetic energy or radiation. Electromagnetic energy travels in space as rhythmic waves.
A rhythmic disturbance that carries energy would be called a mechanical wave. A sound wave or a blast wave (or even a seismic wave) qualifies as a rhythmic disturbance. (Later with the light, okay?) Sound - or any of those other waves - involves the compression and rarefaction of air (or another fluid) or a solid, to transmit the harmonic motion. Let's look at, say, a vibrating guitar string. The string oscillates in air, and the rhythmic motion of the string as it moves back and forth creates sound. The string actually compresses the air in front of it an creates a little "mini-vacuum" behind it as it's moving forward. That space behind the string is rarefied air. The string is moving fast enough that the zillions of tiny air atoms and molecules can't instantly fill in behind that string. A blast wave from an explosion or a seismic wave works the same way. Also, there are different mediums through which the energy is going to be transferred. The medium conducts the energy. The energy is actually transferred into the medium in order to travel through it. Electromagnetic energy may not qualify to be part of this answer under the description set down in the question. The word "disturbance" suggests a medium through which the energy is propagated. Electromagnetic energy, like radio waves or light for instance, require no medium through which they must be transmitted for them to propagate. And as far as light creating "a rhythmic disturbance that carries energy" being true, think about it and come to your own conclusion. Certainly light can move through air or other media, and it interacts with the media, too (losing energy as it does). But a bit of a debate might ensue as to whether or not something like light is actually a "disturbance" as was asked. Light is moving energy - electromagnetic energy. Make no mistake about that. But if light is moving through deep space, what is the "disturbance" involved? Does it have something to do with spacetime?
Wave
A wave is a rhythmic movement that carries energy through matter or space.
Waves
Peristalsis is the movement of food through the alimentary canal, caused by rhythmic contractions of the muscles therein.
OESAPHAGUS carries food from the mouth to the peristalsis bands pushing the food downwards through a movement called peristaltic movement.
Intestines are lined with what are called smooth muscle tissue. These muscles differ primarily from the muscles attached, for example, to your joints in that their movement is rhythmic and involuntarily controlled. (The heart is another example of smooth muscle movement.) It is this rhythmic, involuntary contraction that moves food through the intestines.
Seawater can be turned into drinkable water through desalination.
To be a true solution seawater must be filtered.
"Actually the muscles around your digestive tract help move food through it." The rhythmic movement of these muscles is technically called peristalsis.
Depends on your particular digestive system. It can, in some people, yes. Peristalsis, the normal rhythmic movement of the intestines, can be speeded up by what they consider to be an irritant, yes.
wave
The only substance that carries out osmosis is water. Osmosis is the movement of water through a semi-permeable membrane from a low concentration of solute to a high concentration of solute in the pursuit of equilibrium across the membrane.