AP® Environmental Science

Free Version

Upgrade subject to access all content


Red Tide Poisonings


When the phytoplankton species, Karenia brevis, experiences an algal bloom, it is known as a red tide. During a red tide, the concentration of toxins released by the plankton reaches levels that can kill fish. Filter feeders such as oysters can become contaminated with these toxins during the process of filtering water for food. People who eat the contaminated oysters can become seriously ill.

Which statement is the MOST accurate about red tides?


The red tide toxins biomagnify in oysters and bioaccumulate in people.


The red tide toxins bioaccumulate in Karenia brevis and biomagnify in oysters and people.


The red tide toxins bioaccumulate in oysters and biomagnify in people.


The red tide toxins biomagnify in Karenia brevis and bioaccumulate in oysters and people.


The retention of the red tide toxin in an organism's tissue such as oysters and people is an example of bioaccumulation.