The optimum temperature preferred for plant growth is

Intussusception is

Maximum elongation takes place in

Study the following statements:
$I.$ $O_2$ helps in releasing metabolic energy,which is essential for growth.
$II.$ Nutrients are required by plants for the synthesis of protoplasm.
$III.$ Change in temperature could be detrimental for the survival of an organism.
$IV.$ Light and gravity do not affect the stages of growth.
Choose the correct option.

Auxanometer is meant for

The phase of maturation is characterised by:
$I.$ Cells attaining their maximal size
$II.$ Proper wall thickening and protoplasmic modification
$III.$ Rapid cell division
Select the correct option.