The job of the cell membrane is to

the job of that is to let nutrients or good things inside and keep the unwanted out. To make sure what the cell needs to survive and reproduce

Explanation:hope this helps

the father in the first generation probably had the recessive colorblind trait in his x chromosome. if he and his wife both had the colorblind trait, even if she had 1 recessive and 1 dominant, then that trait would be passed on to their kids.

(since you didn't attach the family tree this is just an assumption)

not sure what it is