Science Words 1 Crossword

a positively charged particle in an atom
a metallic element present in bone
exposure to the sun's rays
the gaseous envelope that surrounds the earth
a type of tree that bears flowers and loses its leaves in winter
an organism with a true nucleus
the control center of eukaryotic cells
an uncharged particle in an atom's nucleus
the position of an organism in an ecological community
forces in the earth that cause the crust to move
an imaginary circle that passes around the earth through both poles
the study of the relationship between organisms and their environment
a type of tree that a bears cones and does not lose its leaves in winter
organelles in the cytoplasm of cells that help produce energy
an organism with no true nucleus