Global warming is primarily caused by an increase in the atmosphere of which gas a. co2 c. ozone b. o2 d. cfcs

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

Contrast how pollination is different among gymnosperms and angiosperms.

The human body needs energy in order to carry out life processes such as breathing. where does the body get this energy? a. from eating food b. from learning about new things c. from lying in the sun d. from sleeping