Study the following statements and select the correct option: Statement (I): Examples of Mendelian disorders are Turner's syndrome and Down's syndrome. Statement (II): Mendelian disorders are caused due to alternation or mutation in the gene. Statement (III): Chromosomal disorders are caused due to the absence or excess of one or more chromosomes

Step-by-step solution

Statement I is incorrect because Turner's syndrome and Down's syndrome are examples of chromosomal disorders, not Mendelian disorders. Examples of Mendelian disorders include haemophilia, cystic fibrosis, sickle-cell anaemia, etc. Statement II is correct as Mendelian disorders are mainly determined by alteration or mutation in a single gene. Statement III is correct as chromosomal disorders are caused due to the absence or excess or abnormal arrangement of one or more chromosomes. Therefore, Statement I is incorrec