Stem Cell terms starting with P

30 terms

pancreas A glandular organ located in the abdomen. It makes pancreatic juices, which contain enzymes that aid in digestion, and it produces several hormones…
Pancreatic beta cells Cells of the pancreas (located in pancreatic islets, or islets of Langerhans) that produce insulin.
Pancreatic polypeptide An endocrine protein produced by islet cells of the pancreas.
Paracrine factors Cytokines or hormones that act on cells or tissues within an extremely limited area.
Parkinson disease (PAR-kin-sun dih-ZEEZ) A progressive disorder of the nervous system marked by muscle tremors, muscle rigidity, decreased mobility, stooped posture, slow…
Parthenogenesis Production of an embryo from an unfertilized egg.
Passage The transfer or transplantation of cells from one culture medium to another.
Peripheral Blood Stem Cell Transplant (PBSCT) A method of separating and collecting stem cells from the circulating blood stream using a process called pheresis.
Phenotype The observable characteristics of an organism, the expression of gene alleles (genotype) as an observable physical or biochemical trait. See Genotype.
Phenotypic characteristics The genetically and environmentally determined physical characteristics of an organism.
Placenta The organ that nourishes the developing fetus in the uterus.
Plasticity A phenomenon used to describe a cell that is capable of becoming a specialized cell type of different tissue.
Platelets Small, irregularly-shaped bodies in the blood that contain granules. These cells are important components of the blood coagulation (clotting) system.
Pluripotent (ploo-RIH-poh-tent) Able to mature or develop in any of several ways.
Pluripotent stem cell (PSC) A single stem cell that has the capability of developing cells of all germ layers (endoderm, ectoderm, and mesoderm).
Pluripotent stem cells Stem cells that can become all the cell types that are found in an implanted embryo, fetus, or developed organism, but not embryonic components of the…
Polar Body A polar body is a structure produced when an early egg cell, or oogonium, undergoes meiosis.
Polarity The observed differentiation of an organism, tissue or cell into parts having opposed or contrasted properties or form.
Population doublings The number of times cells growing in vitro have increased the total number of cells by a factor of 2 compared to the initial number of cells.
Post-implantation embryo Implanted embryos in the early stages of development until the establishment of the body plan of a developed organism with identifiable tissues and organs.
Pre-implantation embryo The very early, free-floating Embryo, from the time the egg is fertilized until implantation in the mother's womb is complete.
Pre-implantation embryos Fertilized eggs (zygotes) and all of the developmental stages up to, but not beyond, the blastocyst stage.
Precursor Cells In fetal or adult tissues, these are partly differentiated cells that divide and give rise to differentiated cells. Also known as progenitor cells.
Preimplantation With regard to an embryo, preimplantation means that the embryo has not yet implanted in the wall of the uterus.
Preparative Regimen The chemotherapy or radiation given before transplant.
Primary germ layers See: germ layer.
Primitive streak The initial band of cells from which the embryo begins to develop. The primitive streak establishes and reveals the embryo's head-tail and left-right…
Primordial germ cell A gamete, that is, a sperm or egg, OR a primordial cell that can mature into a sperm or egg.
Progenitor cell A progenitor cell, often confused with stem cell, is an early descendant of a stem cell that can only differentiate, but it cannot renew itself anymore.
Proliferation Increase by frequent and repeated reproduction; growth by cell division.