As there are no answer choices, I'm going to answer this just based off my knowledge
Analogous structures suggest convergent evolution because they have both evolved from a set of species but for different reasons and from different causes.
The answer would be: <span>secretes mucus that is not identical to stomach mucus
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Stomach cell lining is protected by a thick mucus that prevents the acid from destroying the epithelial cells. But the mucus that secreted by the esophagus is different than the stomach. That makes esophagus can't protect itself from the stomach acid.
A cellular organelle is a structure in the cell that performs a specific function.
Nucleus - stores cell's DNA; DNA replication occurs here
Ribosome - produce protein; "factories" of the cell
Mitochondria - breaks down food for energy to be used by the cell; "powerhouse" of the cell
Vacuole - store materials such as food, water, sugar, minerals, and waste products
Endoplasmic reticulum - carry materials throughout the cell; "transport system"
Answer: natural killer cell
Explanation:
Natural killer cells are referred to as the granular lymphocytes which play vital roles in the immunity against viruses. It doesn't need antigenic activation in order to detect and kill pathogens.
When an enemy cell is present, a natural killer cell secretes perforins, which bore a hole in the enemy cell membrane.