What were the three large, flightless birds with similar features found on different continents, Australia, Africa, and South America?

Which of the following is true of photosynthesis? a)carbon dioxide is a reactant b)water is a product c)most reactions within this process are exothermic d)oxygen is a reactant

Which of the following produces carbon dioxide? a. plants b. animals c. decomposers d. all of the above

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes