横向
1
Unit of force
5
Form of thermal energy
6
Group of similar cells
9
Smallest unit of an element
10
Curved glass that refracts light
纵向
2
Blocking of light by a celestial body
3
Gas essential for breathing
4
Force that attracts objects together
7
Basic unit of life
8
Element found in all living things
11
Center of an atom or cell
12
Measure of matter in an object