Select from:
[i] scales.
[ii] gums.
[iii] cuticle layer.
[iv] mucous membranes.

Answer the following question given this paragraph: The mouth and nose are not lined with skin. Instead, they are lined with mucous membranes . Other organs that are exposed to the outside world, including the lungs and stomach, are also lined with mucous membranes. Mucous membranes are not tough like skin, but they have other defenses. Q: What is in the inside of your mouth and nose instead of skin? A:
Answer:
[iv]