Scientists have concluded that large mammals, such as the woolly mammoth, roamed the earth before the ice age. how do we know that the woolly mammoth was alive in the ice age?

Will someone me with this.. specialized cells which perform a particular function form: tissues organs or organism

Variety of living organisms; includes genetic, species, and ecological types.

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