Across
1
Molten rock beneath Earth surface
3
Unit of electric potential
4
Icy body with a tail near the sun
5
Unit of energy
7
Nerve cell in the brain
10
Unit of heredity
11
Reddish electrical conductor
Down
1
Natural satellite of Earth
2
Gas essential for breathing
4
Basic unit of life
6
Particle of light
8
Force that attracts objects together
9
Path of a planet around the sun