Both autotrophs and hetrotrophs require a source to produce or make food. *
O Hydrogen
O Oxygen
O Carbon
O Nitrogen

What was the land like over 500 million years ago? what was under the sea?

Consider the skeleton. which skeletal system is represented by the shaded portion of the skeleton? spongy skeleton compact skeleton axial skeleton appendicular skeleton

Which of the following describes how binary fission and mitosis are similar? a)they are both used for growth or repair b)they both break down membrane-bound nuclei c)both invoke the replication of a single stand of dna d)both replicate genetic material