Humans (modern species, Homo sapiens) first appeared during which period?

Quaternary

Tertiary

Permian

Cambrian

Study the diagram of a cell. which structure is found only in plant cells and functions in the process of photosynthesis? w x y z

9. the history of life on earth is recorded in

Which of these is an example of land degradation? a. containers designed to store pollutants leak. b. fertilizers provide too many nutrients to crops. c. garbage is buried so the land can be reclaimed later. d. a drought kills all the plants in an area, leaving bare land