Please help I'll mark brainliest

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?

What are the fixed alleles in the human species? o a. the alleles that are on the most chromosomes b. the alleles that change most often 000 c. the alleles that no one has d. the alleles that everyone has

The illustration shown is an ovum, a female sex cell. a mutation in this cell may be passed to the woman’s offspring during a) birth. b) mitosis. c) dna replication. d) sexual reproduction