What is the early phase of the star called once the gas and dust begin to coalesce?

the backbone of the dna and rna compound is sugar phosphate.

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.

the correct answer is 2 and 4