I have searched everywhere, but I have not found the proposals of the question, but I will explain to you what is the endoplasmic reticulum so that you can answer it.
The endoplasmic reticulum is a eukaryotic organelle located in the cytoplasm.
The endoplasmic reticulum is a network of membrane tubules (often interconnected) scattered throughout the cytoplasm of eukaryotic cells. Its membrane, which alone represents more than half of the cellular membrane system, is in contact with the nuclear envelope.
The endoplasmic reticulum can be:
Granular (or rough) (RER) that is to say associated with ribosomes.
Smooth (SER).
The granular endoplasmic reticulum is the place of synthesis (in the associated ribosomes) of the proteins secreted outside the cell and of the proteins and lipids constituting the membranes of the cellular organelles. Golgi, lysosomes, mitochondria, nucleus, ribosomes, vesicles ...). It participates in the correct folding of the proteins that have just been synthesized.
The smooth endoplasmic reticulum participates in cellular metabolism, synthesizing lipids and storing calcium.
Explanation:
Skin cells are specialized to be quickly shed and replaced, and do not have much mitochondria (which helps produce energy). Muscle cells, conversely, have lots of mitochondria because they need energy to produce movement.
A skin cell should proliferate very well and at the same time be protected against UV radiation, it would be important to have a function in which is cell is flexible, but also comparably hard.
A muscle cell needs a huge metabolism, a certain way to function, UV protection on the other side is really not its business.
First off, know that the whole division into kingdoms idea has been removed. All living creatures are now separated into domains: Bacteria, Archaea, and Eukarya. Still, I can provide a few for each category.
Monera is all the bacteria and archae bacteria in the world. They are all prokaryotes and therefore have no nucleus. Some examples are the certain diseases, such as Streptococcus pneumoniae (the bacteria that causes pneumonia) and Micobacterium tuberculosis (which causes tuberculosis).
Fungi are all the fungi of the world, all of which are eukaryotes that exist in both diploid and haploid stages. They include all the mushrooms of the world and molds like the bread mold, Rhizopus stolonifer.
Protists are extremely diverse, many being eukaryotes, though some are prokaryotes, and some being unicellular while others and multicellular. They are divided into three categories, protists (animal-like), which include Amoeba, algae (plant-like), which include Ulva, and fungus-like, which include chytrids.
Gold is a nonrenewable resource
