Rule 1. aufbau rule - energy levels filled so lowest energy level filled first.
Rule 2. pauli exclusion principle - maximum of 2 electrons may be placed in each energy level. Provided the spins of electrons are of opposite sign.
Rule 3. hunds rule - when energy levels are equal one electron is added to each energy level in turn with their spins unpaired until each energy level has one electron.
Answer:
come on yu can do thi you just need to try a little harder and stop asking us to answer all your questions just try.
Explanation:
False
crossing over occurs in prophase 1 of meiosis 1. The significance of this crossing over is to ensure cell differentiation. If this occurred in prophase two it means the cells in meiosis 1 will be identical.