Consider the normal activation of the gene for polygalacturonase in model 3. what is the end result of activation of this gene

The end result of the activation of this gene is the softening of the fruit. The activation of this gene ends up in the production of a protein which is the enzyme polygalacturonase. This enzyme's activity is to degrade pectin, which is one of the polysaccharides responsible for forming and strengthening the cell walls of the plants. By activating this gene, more enzymes are produced, therefore, more pectin is destroyed. This causes the cells walls to weaken and the fruit to soften. 

What some science videos to you