Examples of reflection. Plane wave, plane surface. The phase of the reflected sound waves from hard surfaces and the reflection of string waves from their ends determines whether the interference of the reflected and incident waves will be constructive or destructive.
The tendency to develop allergies is often hereditary, which means it can be passed down through genes from parents to their kids. But just because you, your partner, or one of your children might have allergies doesn't mean that all of your kids will definitely get them, too.
A lot, as it turns out. Allergies and asthma often occur together. The same substances that trigger your hay fever symptoms, such as pollen, dust mites and pet dander, may also cause asthma signs and symptoms. In some people, skin or food allergies can cause asthma symptoms. This is called allergic asthma or allergy-induced asthma. James T C Li, M.D., Ph.D., a Mayo Clinic allergy specialist, answers questions about the link between allergies and asthma.