Parotoid gland

It can secrete a number of milky alkaloid substances (depending on the species) known collectively as bufotoxins, which act as neurotoxins to deter predation.

A study of the parotoid glands of the Colorado River toad in 1976 found that the parotoid glands were "composed of numerous lobules", each of which is a separate unit with a lumen surrounded by a double cell layer.

The study found that the outer cell layer resembled smooth muscle cells, with some organelles hypothesised to "function in some aspects of venom synthesis, active cellular transport and contraction in the discharge of the secretory product".

[2] Parotoid glands are sometimes said to be wart-like in appearance, though warts are abnormal growths caused by viral infections while parotoid glands are normal, healthy parts of the animals that bear them.

The vague similarity in appearance, however, is the reason behind the mistaken belief that touching a toad causes warts.