What is the highest level of organization that is represented in the photograph?
organ
organism
ecosystem
population

What is the main reason that attitudes are more often revealed in spoken rather than written language? a. in writing, we try to put the "best face" on what we write. b. we speak far more often than we write. c. in writing, we can more easily conceal our attitudes. d. in spoken language, we are often careless in our use of words.

Which of the following is a reason why early living organisms on earth could not have survived on the surface? 1. the lack of an ozone layer 2. the lack of oxygen in the atmosphere 3. the fact that these organisms were single-celled

Which example best describes a reflex action? a. eating food when hungry b. coughing when the throat is irritated c. bending down to lift a heavy object d. going for a walk outside