Cell (biology) made up of cellulose, fungi cell walls are made up of chitin and bacteria cell walls are made up of peptidoglycan. A gelatinous capsule is present in some bacteria outside the cell membrane and cell wall. The capsule may be polysaccharide as in pneumococci, meningococci or polypeptide as "Bacillus anthracis" or hyaluronic acid as in streptococci. Capsules are not marked by normal staining protocols and can be detected by India ink or methyl blue; which allows for higher contrast between the cells for observation. Flagella are organelles for cellular mobility. The bacterial flagellum stretches from cytoplasm through the cell membrane(s)
Epiblast-derived stem cell Epiblast-derived stem cell After the blastocyst stage, once an embryo implanted in endometrium (in case of rodent), the inner cell mass (ICM) of a fertilized embryo segregates into two layers: hypoblast and epiblast. The epiblast cells are the functional progenetors of soma and germ cells which later differentiate into three layers: definitive endoderm, mesoderm and ectoderm. Stem cells derived from epiblast are pluripotent. These cells are called epiblast-derived stem cells (EpiSC) and have several different cellular and molecular characteristics with Embryonic Stem Cells (ESC). Pluripotency in EpiSC is essentially different from that of embryonic stem cells. The pluripotency of EpiSC