Is IQ inherited?

I have moved my blog to www.spotalks.com, please go to that link.

This is the question which boggles my mind for many years.In India,people from certain communities are considered to be intelligent.I kept on thinking whether IQ is inherited.If IQ is inherited children from brilliant father and mother has to be intelligent.We see too many children who are very bright has intelligent father or mother.But there are exceptions.So what actually determines the child becoming intelligent.I was reading one of the psychologybook regarding the cognitive functions it even agrees that small part of IQ is related to child's inheritance.
Research finding about the cognitive functions of child says that socio-economic condition of the child plays the vital role in determining IQ of the person.Everybody is born with empty head,its the circumference which shapes us.Deep within,we know already that we are perfect just as we are right now.Abdul kalam was privileged to work with the great minds of India like vikram sarabhai,satish dhawan etc.He himself agreed that his circumstances shaped him.Even if all the people are brought in the same circumstances not everybody shines very well in this world. If it so Darwin's theory of natural selection goes wrong.
Brain studies shown that the left and right sides of the brain are accessed at different speeds and in varying sequences,in different people.Actually left brain is meant for analytical skills,memory,etc and right brain is for innovation,creative,etc.Then why parents and elders are asking us to work hard.If every person has different potential,what will the hard work does.This question is answered by saint thiruvalluvar in 300 BC.Thirukkual says that even if God neglects us by giving poor mind power or ability,If we work very hard and persevere in any endeavour.We will surely reap the fruit of our hard work.So we believe in hard work.