Which metalloid has five valence electrons in the fourth electron shell? antimony
germanium
selenium
arsenic

Indica el nombre y la fucion de los vasos sanguineos que entran y salen de los riñones

Plants that have reproductive structures called cones are?

Why do leaves change color in the fall? green pigments break down and no longer mask the color of chlorophyll. chlorophyll breaks down and no longer masks the colors of other pigments. red- and yellow-colored pigments grow and mask green-colored chlorophyll. green-colored chlorophyll breaks down and turns red and yellow.