The lungs are a. divided into seven lobes b. connected by the mediastinum c. divided into nine lobes d. separated by the mediastinum

True or false: determining the source and motive of an ad for a health product will you decide whether the ad is a reliable source of health information.

True or false a fertilized cell divides many times to form an embryo

Viruses use the host's machinery to make copies of themselves. however, some human viruses require a type of replication that humans do not normally have. for example, humans normally do not have the ability to convert rna into dna. how can these types of viruses infect humans, when human cells cannot perform a particular role that the virus requires? a) the virus causes mutations in the human cells, resulting in the formation of new enzymes that are capable of performing these roles. b) the viral genome codes for specialized enzymes not in the host. c) the virus infects only those cells and species that can perform all the replication roles necessary. d) viruses can stay in a quiescent state until the host cell evolves this ability.