Answer:
1-a 2-a 3-a
1. The first living organism in a food chain is
a) producers
b) primary consumers
c) heterotroph
d) chemosynthesizer
2. The second living organism in a food chain is generally...
a) herbivore
b) carnivore
c) detrivore
d) a photoautotroph
3. Plants use nitrogen to grow and are generally helped by cycling N from the air to the land by bacteria in a process called...
a) nitrogen fixation
b) denitrification
c) decomposition
d) emmigration