Iodine is necessary for the synthesis of which hormone?

The growth of pollen tubes towards ovules is due to:

In which lobe of the cerebrum are the auditory and olfactory centers located?

Electrical impulse travels in a neuron from

$(a)$ Name the part of the brain which controls:
$(i)$ voluntary actions,
$(ii)$ involuntary actions.
$(b)$ What is the significance of the peripheral nervous system? Name the components of this nervous system and distinguish between the origin of the two.

Name two tissues that provide control and coordination in multicellular animals.