When two atoms<span> each need additional </span>electrons<span> to fill their valence shells, but neither is electro-negative enough to </span>steal electrons<span> from the other, they can form </span>another kind<span> of chemical </span>bond<span> called covalent </span>bonds<span>. In a covalent </span>bond<span>, two </span>atoms<span> move closer to share the </span>electrons<span>.</span>
Answer:
The thin external covering is similar to the Cell Membrane. The organelle with a texture like sandpaper is the rough endoplasmic reticulum (ER)
They allow the section of dna to match up with the plasmid in the right position