The process by which organisms with traits that are better suited to their environment tend to survive and reproduce, passing those traits to future generations.

A feeling of discomfort in the stomach, often accompanied by the urge to vomit.

The death of cells or tissues in the body, often due to injury, infection, or lack of blood supply.

Referring to tissue that has died or is undergoing necrosis.

A situation in which the presence of one factor reduces the effect of another factor, often seen in scientific experiments.

A specialized cell in cnidarians, such as jellyfish, that contains a toxin used for capturing prey or defense.

A type of roundworm belonging to the phylum Nematoda, many of which are parasitic in plants and animals.

Infection or disease caused by nematodes, particularly parasitic roundworms.

A group of bacteria that move and feed by forming complex, multicellular fruiting bodies and produce enzymes to degrade organic matter.

A genus of free-living amoebae, some species of which can cause severe brain infections in humans.