This week’s new questions

Why do we have nerve endings in our teeth when they seem to serve no useful purpose? And when doing strenuous exercise, why does it seem to help to call out the number of repetitions?

4 January 2023

Sore Tooth Decay. Dental Care And Pain; Shutterstock ID 1895847487; purchase_order: -; job: -; client: -; other: - — Andrey_Popov/Shutterstock

Why do we have nerve endings in our teeth? They seem to serve no useful purpose.

Bruno Cappelli,

Melbourne, Australia

2CTJXXG Male fitness instructor with women lifting weights while standing in yard — Westend61 GmbH/Alamy

When doing strenuous exercise such as weightlifting, it seems to help to call out the number of repetitions. Why?

Catherine de Lange,

London, UK

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