In $1772$, Joseph Priestley demonstrated that

Fill in the blanks with the suitable words selecting from those given in the bracket.

For testing starch on treatment with _____, it gives a blue colour.

(Lacrymal, Amnion, Iodine, Glucose, Natality rate, Mortality rate, Oestrogen, Gland, Birth womb) 

Fill in the blank by choosing the most appropriate word from the box given below.

All animals, directly or indirectly, depend on _____ for food. (Herbivores/Carnivores/Plants)

(adults, leaves, birds, stomata, sense, kittens, snakes)

The plants breathe in through the _____ present in the leaves.