In amino acid monomers, the side group (r) is covalently bound to:
a. the alpha-carbon.
b. the carboxyl carbon.
c. the amino nitrogen.
d. the hydroxyl oxygen.

a. The alpha-carbon

Explanation:

An amino acid is an organic molecule that contains a carboxyl (COOH) and a amino (NH2) group. It has a central carbon called as alpha carbon.

The carboxyl and amino groups are attached to the the alpha carbon. Apart from them, a side chain denoted by "R" is also covalently attached to it. Side chain varies in each amino acid and it imparts the unique properties to the particular amino acid.

bc blah

explanation:

bc blah

1. a host loses nutrients to a parasite

2. a parasite only benefits when the host is alive (cause if the host dies the parasite dies with it )

3. producers to consumers

4. the tapeworm is a parasite

5. they convert energy from the sun (photosynthesis)

6. sunflower-robin (i think im 80% sure)

7. producer

8. consumer

9. prey

10. fresh water snails ( cause the green algea is the producer and the snails are the primary consumers and the small fish consumer so is the big fish)