Across
1
Second lightest element
5
Biological catalyst
6
Blocking of light by a celestial body
Down
2
Center of an atom or cell
3
Measure of matter in an object
4
Naturally occurring inorganic solid
7
Unit of heredity
8
Form of thermal energy
Second lightest element
Biological catalyst
Blocking of light by a celestial body
Center of an atom or cell
Measure of matter in an object
Naturally occurring inorganic solid
Unit of heredity
Form of thermal energy