Which picture shows geothermal energy?
A) A
B) B
C) C
D) D

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

Which of the following molecules can be broken down into simple sugars? a. nucleic acid b. protein c. lipid d. carbohydrate

Plants need carbon dioxide from their environment to produce glucose during which stage of photosynthesis?