Final answer:
In Texas, individuals 21 years or older can ride a motorcycle without a helmet if they have completed a motorcycle safety course or have adequate medical insurance.
Step-by-step explanation:
In Texas, a person is required to wear a motorcycle helmet unless they are 21 years or older. However, there are additional conditions that one should be aware of to lawfully ride without a helmet. Individuals over the age of 21 are allowed to ride without a helmet only if they complete a motorcycle safety course or can provide proof of adequate medical insurance coverage. It's important for riders to be aware of these regulations for their safety and to comply with Texas law.