"why is it difficult to grow bordetella pertussis in a laboratory"

It is difficult to grow bordetella pertussis in a laboratory because of its inability to grow on ordinary laboratory media such as nutrient agar or macconkey agar. The organism will only grow on specialized media supplemented with charcoal, blood (20%), potato (starch) in order to absorb toxic substances which can inhibit its growth in the agar.

phaneritic textures in which phaner means visible so phaneritic textures are standard of impertinent volcanic rocks. these rocks crystallized gradually under the surface of earth. when the magma cools deliberately then the ores have chance to develop and produce long crystals.

you know they are heterozygous for a trait because they have it as jj or jj.