Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
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Question: Question: Is kREX2 essential for either procyclic or bloodstream form Trypanosoma brucei?
Answer: KREX2 is a U-specific exonuclease that is dispensable for RNA editing in vivo in T. brucei BFs and PFs. This result suggests that the U deletion activity, which is required for RNA editing, is primarily mediated in vivo by KREX1 which is normally found associated with only one type of editosome. The retention of the KREX2 gene implies a non-essential role or a role that is essential in other life cycle stages or conditions.

Answer: no


Question: Question: Does renal excretion of fluoride after fluoride mouth rinse in children?
Answer: After the use of a fluoride mouthwash, in children, there is a statistically significant increase of fluoride ion in urine, which can be attributed to the application of this product.

Answer: yes


Question: Question: Does sphingosine 1-phosphate induce sinus tachycardia and coronary vasoconstriction in the canine heart?
Answer: These results may provide a clue to better understanding the physiological as well as the pathophysiological regulation of sphingosine 1-phosphate in the heart.

Answer:
yes