横向
1
Biological catalyst
4
Compound containing oxygen
8
Preserved remains of ancient life
10
Force that attracts objects together
12
Unit of heredity
13
Smallest unit of an element
纵向
2
Basic unit of life
3
Unit of energy
5
Infectious microscopic agent
6
The Red Planet
7
Gas essential for breathing
9
Mass per unit volume
11
Group of similar cells