Which statement would most likely be true of the next stage of fetal development

Which of the following occurs most often in a population when genetic variation and overproduction are present? some organisms have a lower reproductive success than others. some organisms have a higher reproductive success than others. some organisms have no reproductive success. some organisms do not have genetic variation.

Genetic disorders can result when sister chromatids fail to seperate properly. during what phase is this problem most likely to occur?

In which part of the body is a ball-and-socket joint found?