What protist changes shape constantly and flows around its food to engulf it?

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen

Hemoglobin is a proton that carries oxygen around your body what is hemoglobin made from

One reason scientists are trying to develop fuel sources from corn and sugar is because these sources are renewable fossil fuels are being depleted these crops can be widely grown all of the above