D)Vacuole and cell wall because animal cells have temporary vacuoles and are small scattered and no cell wall
Answer:
It's 3!
Explanation:
There must be genetic differences so the best fitted organisms will survive. If they were all the same then no one would be best fitted and Natural Selection wouldn't be able to occur
It's not 1 because a food shortage isn't required, there's always competition for food sources
It's not 2 because there doesn't need to be a change in the environment for natural selection, just for evolution.
And it can't be 4 if 1 and 2 are wrong!
Hope this helped!
The answer is the last one Cancer treatment
Explanation:
The nucleus contains two types of subatomic particles, protons and neutrons. The protons have a positive electrical charge and the neutrons have no electrical charge. A third type of subatomic particle, electrons, move around the nucleus. The electrons have a negative electrical charge.