They all work in different ways but they all work together. For example, the Skeletal and muscular system will help you move away from danger or fire. Although, the nervous system sends messages to the brain that there is danger or fire.
I think so it is molecules
When an yeast cell undergoes fermentation, ethanol and carbon dioxide is produced.
Answer:
The origin of the rectus abdominis is the abdomen of the human body.
The answer would be b, emigration because emigration means to leave an area to go to another one, and all those factors would result in the animals leaving.