What do the dots in this image represent? Ionic bonds in water
Covalent bonds in water
Shared valence electrons
Unshared/lone pairs of valence electrons

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.