An externality is defined as a benefit or a loss that occurs to a third party due to some external reasons. The party has no control over the creation of the benefit or loss. It can be both negative or positive. Negative externality is a loss caused to the party whereas positive externality is a benefit caused to the party.
Here, the river is being polluted due to paper manufacturing industry. It means that the river is incurring a loss due to an external factor. Hence, this situation would be considered as negative externality.
She notices that movement of large molecules into and out of the cell is ... and out of the cell is disrupted when she damages one specific type of macromolecule. ... The macromolecule which has she most likely damaged would be a protein.
