There are many things that must occur for you to see. You must have optic nerves that are in tact for example.
colour must occur in one of three ways: light must be refracted off a surface. light must pass through a fliter or prism or liquid. light must be projected. Of the correct wavelength to produce a colour. the light must then pass into the back of the eye and hit the rods and cones at the back of the eye. Then the brain must process the image through the optic nerve.
It must enter our eyes.
Mitosis must occur in budding.
it allows you to see close ups of the moon and other planets to see the events that occur on special occasions
The changes to the rock must occur in solid form.
mating must happen randomly
US marriages must be dissolved in the state in which they occur.
What processes must occur to produce an igneous rock
Transcription must occur .
Two objects must be touching and it has to transfer heat
what type of conditionals must be present for mineral fossilization to occur
Oxygen gas must be present for a combustion reaction to occur.