meristem cells are unspecialized cells,similer to our own stem cells in our bones that make red blood cells.
What do scientists do to adult cells to make them behave like embryos?
In the adult intestines, the stem cells that generate new cells to protect the tissues are located in the intestinal crypts. These stem cells are found at the base of the crypts and continuously divide to produce new cells that migrate upwards to replace the older cells that line the intestinal surface.
Yes and No. The only big difference is the procedures used in harvesting adult stem cells is considered legal and safe. There's no need to kill a human embryo. Adult stem cells can be harvested from cord blood or human bone marrow. But embryonic stem cells are able to make more kinds of cells than adult stem cells.
The simple tissues, such as parenchyma, collenchyma, and sclerenchyma, correspond closely to the typical unspecialized plant cell. These tissues are composed of cells that retain the basic characteristics of a plant cell, like a cell wall and a large central vacuole, while also performing specialized functions like support, storage, and photosynthesis.
meristem cells are unspecialized cells,similer to our own stem cells in our bones that make red blood cells.
What do scientists do to adult cells to make them behave like embryos?
Phloem tissue consists of: conducting cells, generally called sieve elements; parenchyma cells, including both specialized companion cells or albuminous cells and unspecialized cells; and supportive cells, such as fibres and sclereids.(attribution: wikipedia, Phloem)
in the digestive tract
in the digestive tract
Stem cells are those which could make up new tissues. Eg. bone marrow stem cells make up blood organelles. Adult stem cells could be used to make tissue that could then be transplanted into human beings.
There are no products that use human cells, whether fetus, baby, or adult cells.
In the adult intestines, the stem cells that generate new cells to protect the tissues are located in the intestinal crypts. These stem cells are found at the base of the crypts and continuously divide to produce new cells that migrate upwards to replace the older cells that line the intestinal surface.
To shorten the amount of numbers they had to write down and to make the scale of the Universe more comprehensible.
Yes and No. The only big difference is the procedures used in harvesting adult stem cells is considered legal and safe. There's no need to kill a human embryo. Adult stem cells can be harvested from cord blood or human bone marrow. But embryonic stem cells are able to make more kinds of cells than adult stem cells.
The simple tissues, such as parenchyma, collenchyma, and sclerenchyma, correspond closely to the typical unspecialized plant cell. These tissues are composed of cells that retain the basic characteristics of a plant cell, like a cell wall and a large central vacuole, while also performing specialized functions like support, storage, and photosynthesis.
Stem cells differ from other kinds of cells in the body. All stem cells-regardless of their source-have three general properties: they are capable of dividing and renewing themselves for long periods; they are unspecialized; and they can give rise to specialized cell types.Stem cells are capable of dividing and renewing themselves for long periods. Unlike muscle cells, blood cells, or nerve cells-which do not normally replicate themselves-stem cells may replicate many times, or proliferate. A starting population of stem cells that proliferates for many months in the laboratory can yield millions of cells. If the resulting cells continue to be unspecialized, like the parent stem cells, the cells are said to be capable of long-term self-renewal.Scientists are trying to understand two fundamental properties of stem cells that relate to their long-term self-renewal:why can embryonic stem cells proliferate for a year or more in the laboratory without differentiating, but most non-embryonic stem cells cannot; andwhat are the factors in living organisms that normally regulate stem cell proliferation and self-renewal?Discovering the answers to these questions may make it possible to understand how cell proliferation is regulated during normal embryonic development or during the abnormal cell divisionthat leads to cancer. Such information would also enable scientists to grow embryonic and non-embryonic stem cells more efficiently in the laboratory.The specific factors and conditions that allow stem cells to remain unspecialized are of great interest to scientists. It has taken scientists many years of trial and error to learn to derive and maintain stem cells in the laboratory without them spontaneously differentiating into specific cell types. For example, it took two decades to learn how to grow human embryonic stem cells in the laboratory following the development of conditions for growing mouse stem cells. Therefore, understanding the signals in a mature organism that cause a stem cell population to proliferate and remain unspecialized until the cells are needed. Such information is critical for scientists to be able to grow large numbers of unspecialized stem cells in the laboratory for further experimentation.Stem cells are unspecialized. One of the fundamental properties of a stem cell is that it does not have any tissue-specific structures that allow it to perform specialized functions. For example, a stem cell cannot work with its neighbors to pump blood through the body (like a heart muscle cell), and it cannot carry oxygen molecules through the bloodstream (like a red blood cell). However, unspecialized stem cells can give rise to specialized cells, including heart muscle cells, blood cells, or nerve cells.Stem cells can give rise to specialized cells. When unspecialized stem cells give rise to specialized cells, the process is called differentiation. While differentiating, the cell usually goes through several stages, becoming more specialized at each step. Scientists are just beginning to understand the signals inside and outside cells that trigger each stem of the differentiation process. The internal signalsare controlled by a cell's genes, which are interspersed across long strands of DNA, and carry coded instructions for all cellular structures and functions. The external signals for cell differentiation include chemicals secreted by other cells, physical contact with neighboring cells, and certain molecules in the microenvironment. The interaction of signals during differentiation causes the cell's DNA to acquire epigeneticmarks that restrict DNA expression in the cell and can be passed on through cell division.Many questions about stem cell differentiation remain. For example, are the internal and external signals for cell differentiation similar for all kinds of stem cells? Can specific sets of signals be identified that promote differentiation into specific cell types? Addressing these questions may lead scientists to find new ways to control stem cell differentiation in the laboratory, thereby growing cells or tissues that can be used for specific purposes such as cell-based therapies or drug screening.Adult stem cells typically generate the cell types of the tissue in which they reside. For example, a blood-forming adult stem cell in the bone marrow normally gives rise to the many types of blood cells. It is generally accepted that a blood-forming cell in the bone marrow-which is called a hematopoietic stem cell-cannot give rise to the cells of a very different tissue, such as nerve cells in the brain. Experiments over the last several years have purported to show that stem cells from one tissue may give rise to cell types of a completely different tissue. This remains an area of great debate within the research community. This controversy demonstrates the challenges of studying adult stem cells and suggests that additional research using adult stem cells is necessary to understand their full potential as future therapies.