What is the function of each of these modifications in the tracheal epithelium? Cilia? Goblet cells?

Answer 1

Cilia wave to move mucus and trapped particles up the trachea to be coughed out or swallowed.

Goblet cells make the mucus that catches the particles.

Answer 2

These are the parts of Human digestive systems. They are found through the food pipe. Cillia is a brush like figure which is meant for the movement of food in the upper parts of the food pipe while it facilitates the movement of bowl in the lower part of the intestine. Cillia also involves in increasing the surface area of the intestinal wall so that to provide more diffusion of materials through it, its diffusion causes acceptance of digested food and water.
Goblet cells are are a kind of very special glands which secrete mucus into our digestive system. They are found like pits and thus it is also a part of digestive system helps in the digestion of food by secreting juices. It is also referred as an endocrine gland.

For further reference please visit :- http://en.wikipedia.org/wiki/Goblet_cell

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