If there are a lot more females then males in a country, there could be a rise in births, and if it is serious it could lead to an overpopulation problem. If there are more males there could be a lack of births, and the infrastructure could be compromised. In both cases specific gender-related jobs could be in short supply or there might not be enough workers for a steady economy.
You could tell them that the food chain is basically something that shows the feeding relationship between different living things. The food chain represents a series of food and energy are transferred from one organism in an ecosystem to another.<span />
