How is the available energy in the marine ecosystem different than the African savanna ecosystem?

Hey me with this one❤☺❤ how do you say that a cell also has a life span and death like an organism? give one example.

Which type of respiration takes place when there is no oxygen present? a. anaerobic b. mitochondrial c. cellular d. aerobica. anaerobic

Abird flies by moving its wings up and down. which two systems are most directly responsible for the movement of a bird's wings? a. skeletal and muscular systems b. respiratory and muscular systems c. skeletal and digestive systems d. respiratory and digestive systems