When two dihybrid individuals are mated, this is called a dihybrid cross. Even though the parents of a dihybrid cross have the same genotype and phenotype, their offspring could show any one of 9 different genotypes and 4 different phenotypes. The phenotypic ratio of offspring produced from a dihybrid cross is 9:3:3:1. To unlock this lesson you must be a Study.com Member.
Sounds are heard by the ear as either being loud or soft. The loudness of a sound in measured in decibels. Decibels refer to the energy produced by that sound. A human can hear sounds ranging from 0.1 decibels, which is very soft, to sound which measure 120 decibels. Younger people can often hear lower volumes better than older people.
1 Know which noises in your environment are damaging (85 decibels or louder). 2  Wear hearing protection whenever you know youâll be exposed to loud noise.  If you canât protect your hearing from the loud noise, move away from it.