Answer: Chromosomes become visible, crossing-over occurs, the nucleolus disappears, the meiotic spindle forms, and the nuclear envelope disappears. ... At the start of prophase I, the chromosomes have already duplicated. During prophase I, they coil and become shorter and thicker and visible under the light microscope.
A specises that is very close to extinction that they are trying to save
I am pretty sure that a point mutation that creates a premature stop codon is called a synonymous mutation. It also can be called silent mutation, if you have it in you option list, feel free to use it, it is the same. That will definitely help you.
Cell walls are thicker than cell membranes, and can therefore support the cell well. They keep a strong boundary for the protection of the cell, but can let water and some nutrients through to nourish and power the cell. Hope this helps! :)