In which of the following is thigmotropic movement best observed?

Auxanometer is meant for

Thigmotropism is best seen in

Find out the correct statement$(s)$.
$(a)$ Growth in plants is internal/intrinsic and open-ended.
$(b)$ Formation of cellular materials is called real or protoplasmic growth.
$(c)$ Plant growth is diffused only during the early embryonic stage.

Nastic movements differ from tropic movements in being

The rate of growth of any organism follows