Solution – three types of ecological pyramids are :

1. Pyramid of numbers – denotes number of individual organisms at each trophic level in an ecosystem. It can be either upright or inverted pyramid .
2. Pyramid of biomass – indicates the quantity of organic matter present at each trophic level in an ecosystem. It can be either upright or inverted pyramid .
3. Pyramid of energy –  tells the total amount of energy present at each trophic level in an ecosystem. It can be either upright or inverted pyramid.