Posture and balance of the body is controlled by

The growth of tendril in pea plants is due to:

What is the movement of a plant shoot towards light called?

$(a)$ Define hormone. Write four characteristics of hormones in humans.
$(b)$ Name the disorder caused by the following situations:
$(i)$ Under secretion of growth hormone
$(ii)$ Over secretion of growth hormone
$(iii)$ Under secretion of insulin
$(iv)$ Deficiency of iodine

Dramatic changes of body features associated with puberty are mainly because of the secretion of:

Which systems in animals work together to provide coordination and regulation?