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.
Genetics: Children born into families where allergies already exist have a higher than average chance of developing allergies themselves. In the UK today, children have a 1 in 5 predisposition of developing an allergy. However, the risk is doubled if one parent has an allergy (particularly if that parent is the mother).If both parents have allergies, the risk is increased to 60-80%. This increased tendency for individuals to develop allergies because of their genes is known as being atopic.Atopy results in an increased risk to any allergy, not just a specific type of allergic disease.t has been suggested that the increase in food allergy might be due to more allergenic foods, such as peanut, in our diet. However, there is no evidence that this has happened, and many cultures traditionally eat high amounts of certain allergenic foods, for example, peanuts in some Asian communities.