Basic structure not defined by Constitution of India

The basic structure doctrine is not defined by the Constitution. It is rather a judicial invention that came through Kesavananda Bharati vs State of Kerala case (1973). Supreme Court said that the Constitution of India has certain basic features that cannot be altered or destroyed through the provisions of amendment, by the Parliament of India, as mentioned in the Constitution of India. 

Judicial review is explicitly provided for protection of fundamental rights under Article 32 and 226. Further under Article 136, Supreme Court may, in its discretion, grant special leave to appeal from any judgment, decree, determination, sentence or order in any cause or matter passed or made by any court or tribunal in the territory of India.