Which of the following marine ecosystems consists of an aphotic zone? a. the intertidal zone b. the open ocean c. the wetland d. the coastal ocean

Enzyme speed up chemical reaction are which type of marcomolecule? a.carbohhydrates b.protiens c.lipids d.nucleic acids

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.

Which of the following particles always has a positive charge? a. electronb. neutron c. proton d. ion