is the backbone of living things, because, since it can bond to itself, it can form these long chains of molecules. *

A. Hydrogen

B. Helium

C. Carbon

D. Oxygen

E. Copper

F. Gold

Parasitism could be considered a form of which of these types of relationships? -mutualism -commensalism -predator-prey -mimicry

How have high taxes on tobacco products impacted the number of people who use them? a. the number of tobacco users has increased. b. the number of tobacco users has decreased. c. the number of tobacco users has not changed. d. the number of adolescent tobacco users decreased, while the number of adult users increased

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