Original: Morphogenetic responses may be induced in organisms by hormones , by environmental chemicals ranging from substances produced by other organisms to toxic chemicals or radionuclides released as pollutants , and other plants , or by mechanical stresses induced by spatial patterning of the cells .
Simplified: Morphogenetic responses may be induced in organisms by hormones , by substances produced by other organisms , or by mechanical stresses induced by spatial patterning of the cells .