How would the human population be different if crossing over did not happen during meiosis

The response is the basis for vaccination. primary secondary tertiary none of the above

Acell goes through cellular respiration and produces atp which it then uses to move a molecule across the cell membrane. how does the energy in the original glucose molecule change during this process? (2 points)

Anurse is caring for a 42-year-old client who is scheduled for an amniocentesis during the fifteenth week of gestation because of concerns regarding down syndrome. what other fetal problem does an examination of the amniotic fluid reveal at this time?