Protein synthesis in bacterial cells usually starts with a: a. cysteine residue. b. phenylalanine residue. c. formylmethionine residue. d. valine residue. e. methionine residue.

c. formylmethionine residue

Explanation:

The initiation codon (5' AUG 3') is present in the P site of the bacterial ribosomes and bind to the tRNA carrying formyl methionine amino acid. The formyl methionine amino acid serves to initiate the process of protein synthesis in bacteria. The initiator amino acid formyl methionine is encoded by genetic code "AUG".  

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms