why is farm land ploughed before sowing seeds

this allows the roots to penetrate deep into the soil

it maintains the air circulation in the soil

the loosened soil helps in the growth of earthworms and microbes. these organism further  loosen the soil and add humus to it

 turning and loosenig of soil bringd the nutrient rich soil to tha top so that plants can use these nutrients.

the microorganism present in the soil enrich its fertility. for example - ryzhobium bacteria replenishes nitrogen content of the soil