Where do electrons get their energy in photosystem II? A. From energy in photons B. From ADP and ATP C. From NAD and NADPH D. From glucose in Calvin cycle

How does the carbon cycle involve an exchange of carbon

Which statement correctly describes other ways in which nebulae and stars are different? a. a star always has a higher density than a nebula. b. stars can form inside a nebula but a nebula can never be produced by any star. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star. reset submit

Which type of neuron stimulates muscles to contract?