Rough Endoplasmic Reticulum: 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.
Smooth Endoplasmic Reticulum: comprises of a tube-like structure located near the cell periphery. These tubules or tubes sometimes branch forming a network that is reticular in appearance. The network of smooth endoplasmic reticulum allows for an increased surface area to be devoted to storage of key enzymes.
The primary function of all lymph nodes is the production of lymphocytes, which help defend the body against microorganisms and against harmful foreign particles and debris from lymph before it is returned to the blood stream. The major clusters of lymph nodes are in six areas.
