Air pollution; smoking in the house
A unique feature of the nucleus is that it disassembles and re-forms each time most cells divide. At the beginning of mitosis, the chromosomes condense, the nucleolus disappears, and the nuclear envelope breaks down, resulting in the release of most of the contents of the nucleus into the cytoplasm.
Answer:
1. Air warms, becomes less dense, it rises
2. Air cools down, increases density (becomes denser), it sinks
Answer:
Move molecules into or out of cells of the body
Explanation:
Move molecules into or out of cells of the body
