The type of bacteria that can grow in the absence of oxygen are called ______.
Anaerobic
Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen.
Saprotrophs are organisms, particularly fungi, which obtain nutrients directly from dead organic matter.
A parasite is an organism that lives within or on a host. The host is another organism. The parasite uses the host's resources to fuel its life cycle.