Answer:
cell theory states that: all living things are composed of one or more cells, the cell is the basic unit of life, and new cells arise from existing cells.
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D would be the correct statement
Keratin, a type of protein that is a basic component of hair, skin and nails and helps create an intact barrier.
A. All four are protist membranes
b. Two are from the engulfed photosynthetic bacterium; one is a protist membrane; the other is from the food vacuole produced by the protist originally containing the bacterium.
c. Four membranes evolved from the protist's cell membrane.
d. All four are bacterial membranes.
e. One is from the bacterium; one is from the protist; one is from the bacterial nuclear membrane; one is from a food vacuole.