In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.
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Question: Question: Indicate the net charge of an amino acid with a neutral R group for a pH value below its pI:
Options: <0> Negative net charge. <1> Positive net charge. <2> Without charge. <3> It is necessary to know the exact pH value to answer this question. <4> It is necessary to know the concentration of the amino acid to answer this question.

Answer: chemistry

Question: Question: The aminoacyl-tRNA synthetases:
Options: <0> They participate in the synthesis of the TRANs. <1> They participate in the maturation of the precursors of the TRANs. <2> They are responsible for the synthesis of amino acids. <3> They are responsible for the interpretation of the genetic code. <4> They synthesize parts of the ribosomes.

Answer: chemistry

Question: Question: On the synthesis of proteins it is correct to affirm that:
Options: <0> Start at the carboxyl end. <1> The mRNA is translated from the 5'-end to the 3'-end. <2> In eukaryotes it takes place in the nucleus. <3> The first subunit of the ribosome to bind to the mRNA is the largest. <4> It does not consume energy.

Answer:
biology