why is it important that all seeds may not require light to grow but all fully grown plants do need light to grow

why is it important that all seeds may not require light to grow but a

1.	why is it important that all seeds may not require light to grow but all fully grown plants do need light to grow
Answer» The cause of the refraction of LIGHT is that light travels at different speeds in different MEDIA. This CHANGE in the speed of light when it moves from ONE medium to another causes it to bend. Refraction is caused due to the change in speed of light when it ENTERS from one medium to another