Drinking alcohol during pregnancy negatively impacts development of the fetus because:
the mother’s body is unable to process alcohol.
alcohol crosses the barrier that the placenta creates.
the mother can no longer produce primary oocytes.
alcohol causes the mother to have facial distortions.

Alcohol crosses the barrier that the placenta creates

Explanation:

Alcohol molecules are small in size and polar. This means they can pass the placental barrier from the maternal blood supply into the fetus. The alcohol levels will accumulate in the fetus more than the mother because the fetus cannot metabolise alcohol and is depends on the mother's liver to breakdown the alcohol. The alcohol will thus accumulate in the fetus longer and have adverse effects such as impeding on the development of the fetus.

what bodys are there orbiting?

sex cells are usually half's then they find another half and make a fertilize egg