Why can plant cells photosynthesiz, but animal cells cannot? a) plant cells have glucose

b) plant cells are autotrphs

c) plant cells have chloroplasts

d) plant cells have ATP

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important

Describe two recent or ongoing space missions.

Which statement describes characteristics of planarians? a they live in oceans, are parasites, and reproduce only sexually. b they live in fresh water, are parasites, and reproduce only asexually. c they live in oceans, are free living, and reproduce sexually and asexually. d they live in fresh water, are free living, and reproduce sexually and asexually.