Viruses are not considered "alive" because they lack many of the properties that scientists associate with living organisms. Primarily, they lack the ability to reproduce without the aid of a host cell, and don't use the typical cell- division approach to replication.
Because they are made to perform two different functions. Cells are part of tissues that are part of organs that perform a certain function. For example, your bone cells are made to make blood cells, so they wouldn’t be in your lungs as well.
Statement D best describes the difference between the way plants and animals obtain energy.
Cyanobacteria released OXYGEN into the atmosphere through photosynthesis
