Question 17 (Mandatory) (0.5 points) Which statement about normal microbiota is TRUE? The body carries 100 times as many microbial cells as human cells. Normal microbiota is restricted to the gut and only plays a role in digestion and vitamin synthesis. The microbiome includes members of a microbial community and the genetic makeup of that community. The majority of microbes in a microbiome can be identified by culturing them in a laboratory. Bacterial species associated with gum disease also always cause Alzheimer's disease.