Which best explained why viruses do not have special structures or enzymes that allow them to make their own food?

Most animal cell membranes have proteins that pump. ions out of the cell and potassium ions into this

Which of the following does not make up ground substance of connective tissue? hyaluronic acid elastic fibers glycosaminoglycan proteoglycan

As the earth formed, the force of gravity increased due to increased mass. what effect did this increased gravity have on the forming planet?