Epithelia are classified by the number of cell layers and the general shape of the cells
I believe animals that possess homologous structures probably evolved from the same ancestor. Homologous structures are similar because of common ancestry. A homologous structure is an example of an organ or bone that appears in different animals, underlining anatomical commonalities demonstrating descent from a common ancestor.
Answer:
D. "always" cover the microscope when not in use.
Explanation:
when you are finished using a light microscope or any microscope in general you always need to put the cover back on it. Mostly, to protect it from any harmful bacteria, light etc. and to keep it clean and, from collecting dust.
Homologous structures are common structures in different species that perform different functions and may have look similar in structure.
Example- The different animals have bones that appear very similar in form and function and seem to be related.