Well in order for chemical digestion to occur period, a enzyme is needed.
In the mouth this enzyme is amylase
Answer:
Dry Mouth (Xerostomia)
Fungal Infection.
Gum Swelling (Gingival Overgrowth)
Inflammation of the Lining Inside of the Mouth (Mucositis)
Mouth Sores (Ulcers)
Taste Changes, Including Metallic Taste.
Tooth Decay.
Tooth Discoloration.
Any fat. Like oil. Fats are hydrophobic, so they resist water and don't mix.
Natural selection is the process that result in the adaptation of an organism to environment by means of selectively reproducing changes in its genotype, or genetic constitution. It is the a key mechanism of evolution. Charles Darwin popularised the term "natural selection" contrasting it with artificial selection, which is intentional, whereas natural selection is not.
To make it simple, let's have a group of beetle composing of green and some are brown as an example. here, there is a variation in traits. Since the environment could not support continuous population growth, not all species can reproduce to their full potential. Green beetles can easily be eaten by other species like birds compared to brown beetles. The surviving brown beetles will then generate brown offsprings because their trait has a genetic basis. Since more brown beetles survive and becomes more common in the population, the process continues until all individuals will eventually be brown. so basically, if you have variation, differential reproduction, and heredity, you will have evolution by natural selection as an outcome.
Lipids are good for making the cell membrane because they are stronger and block out things that should not be getting in out, for instance lipids mainly only let water and gases pass through.