Answer:
Rough endoplasmic reticulum (RER), series of connected flattened sacs, part of a continuous membrane organelle within the cytoplasm of eukaryotic cells, that plays a central role in the synthesis of proteins.
D. fingernails
Skin, hair, and vertebrae are all the outer layer of the body and protect the body. The fingernails aren't part of that.
B) Billowy sheep-like clouds.
Cells -> Tissues -> Organs -> Organs systems -> Organisms
