Population structure is the thing that the populationis made out of, or it indicates what is the make up of a population. It partitions the diverse sex of a place or group particularly guys and females of various age gatherings. The population pyramid demonstrates how the guys and females of various age assemble is separated, it is the graphical outline of the division of the two. The following is a case of a populace pyramid. The figure above shows how the two sexual orientation with various age bunches are isolated impressively. The most stretched out bar at the left side implies that the biggest populace in Kentucky are guys with the age of 20-24 years of age. While on the female side, the biggest population among the age bunches are 0-4 years of age. The reason of the substantial number of guys in Kentucky is on the grounds that it is the area of a huge army base. So the bars as an afterthought decide the sex and gauge the quantity of them while the center part decide the age of the diverse gatherings. Population Density is the quantity of people per unit zone. Population density is controlled by isolating the population by the zone. For instance, if the Philippines has a population of 103 million individuals and a territory of 300,000 km so the population density is 323.33 people for every square kilometer. There are two reasons that can influence population density, the inputs and outputs. The data sources can be high birth rate or migration. High movement or birth rate can influence the density in the event that it isn’t adjusted with the output which is death or migration. On the off chance that there is high sources of input and low output, it can cause overpopulation. Energy flow is the exchange of energy from trophic level to another trophic level. Sunlight based energy is exchanged from the sun to the plants or the makers and will be taken in by the essential producer while the energy exchanges, it just exchange 90% of energy will be lost because of respiration. So the principal consumer just get 10% of energy while 1% for the secondary and just 0.1% remaining for the tertiary consumer. A great deal of energy is lost between trophic levels, thus the last consumer gets the most minimal energy.