Light acts like when it bounces off surfaces, and acts like it bends around objects.

The current thought on the structure of the cell membrane is: a. a static phosphate sandwich of lipids b. a fluid-mosaic of phospholipids and proteins c. a bilayer of proteins with static lipid molecules d. an impermeable bilayer of protein molecules e. a static and permeable phospholipid single layer

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.

All ova contain sex chromosomes corresponding to: x y xx xy