Across
1
Unit of heredity
3
Gas form of a liquid
5
Substance with pH below 7
6
Group of similar cells
8
Nerve cell in the brain
11
Center of an atom or cell
Down
1
Force that attracts objects together
2
Compound containing oxygen
4
Blocking of light by a celestial body
7
Glass that splits light into spectrum
9
Tissue that contracts for movement
10
Natural satellite of Earth