0
Stem Cells
Stem cells are a biological cell that can turn into a specialized cell, and then divide to create more.
678 Questions
What are the differences between embryo and adult stem cells?
Adult stem cells are harvested from newborn's cord blood or human bone marrow while embryo stem cells come from the inner cell mass of a human embryo. No fetus is killed to use the stem cells, but the embryo cannot function and must be destroyed without a inner cell mass.
Why we shouldn't use embryonic stem cells?
Many scientists and people say that embryonic stem cells have the potential to cure many diseases, such as cancer. On the contrary, many other people are discomforted by the idea of destroying human embyos for a scientific purpose. They argue that life begins at conception, and that no person has the right to kill any form of human life. Many people believe that only God gives life, and only God should take it.
To enable ES (embryonic stem) cells to grow outside of the embryo they have to be cultured in the presence of embryonic fibroblasts, which provide nutrients to keep
the ES cells in an undifferentiated state. In this state the cells can
grow indefinately. When these cells are removed from the fibroblasts (or
medium which has been conditioned by these cells) the ES cells
spontaneously differentiate into a range of cell types. In theory, ES
cells can form into any of the cells within the body. However, in practice
only a few pure cell types have been produced (e.g. neuronal and blood).
What is the adaptation of a stem cell?
Rhizomes are underground perennial stem eg Lily.
Tubers are swollen stems (terminal portions of underground rhizomes) found in potatoes. This is important for perennation (The ability of a plant to survive from year to year).
Corms are swollen underground stem base that has been modified into a mass of storage tissue.
Stolons are above ground stems often called runners. Important for vegetative reproduction; new plants are formed at the nodes eg Strawberries.
Stems can be adapted in succulents to store water.
Stems can also be parasitic and strangle other plants
What can stem cells do that other cells can not do?
Stem cells has the capability to regenerate and develop into any kind of tissue or organ, when supported with the external nutrients. So they are called as totipotent.
There are two kinds of stem cell
a)adult stem cells
b)embryonic stem cells.
There are various researches going on in this area .
How might stem cells be used to treat disease?
Stem cells are usually totipotent or pleuripotent cells. As such, they can undergo differentiation, according to the conditions provided, to give different types of cells. Basically, they have capability of producing specific tissues.
Scientists believe that stem cell therapy can very much effect the treatment of illnesses. Presently, bone marrow transplants, which are used to treat leukemia, are also a type of stem cell therapy.
Medical researchers are trying to make stem cell therapy able to cure diseases such as Parkinson's disease, cancer, spinal cord injuries, muscle damage, etc.
How do stem cells differentiate from other cells?
Stem cells are different from other cells in the body in several notable ways. They can divide and renew themselves many times, whereas other cells are more limited in their divisions. And when those stem cells divide, the new cells can become specialized if necessary. Stem cells have no assigned function in the body, but through the process of specialization, they can take on roles in any of the body's tissues. These type of cells can be derived from human embryos or from certain spots in the adult human body.
How can adult and embryonic stem cells cure diseases?
Nothing has been definitively cured yet, mainly due to the ban that a lot of governments (America's included until recently) had on using embryonic stem cells to do research. Now that the ban has been lifted, there are sure to be a LOT of cures heading our way. Scientists are hopeful that they will be able to cure diseases such as diabetes and Parkinson's, as well as help victims with spinal cord injuries. The future of stem cell research is going to be very exciting.
What are the three types of stem cells in adults?
The three types of stem cells in adults are hematopoietic stem cells (found in bone marrow and produce blood cells), mesenchymal stem cells (found in various tissues like bone marrow and fat, can differentiate into bone, cartilage, and fat cells), and neural stem cells (found in the brain and spinal cord, can differentiate into neurons and supporting cells).
How. An stem cells help the patient?
In stem cell transplants, stem cells replace cells damaged by chemotherapy or disease or serve as a way for the donor's immune system to fight some types of cancer and blood-related diseases, such as leukemia, lymphoma, neuroblastoma and multiple myeloma.
Where are therapeutic stem cells obtained from?
A stem cell is a cell that has the ability to continuously divide and differentiate (develop) into various other kind(s) of cells and tissues. Like a blank microchip that can ultimately be programmed to perform any one of a number of specialized tasks, stem cells are undifferentiated, 'blank' cells that do not yet have a specific physiological function. When the proper conditions occur in the body or in the laboratory, stem cells begin to develop into specialized tissues and organs. Stem cells are also self-sustaining, replicating through cell division.
These unique characteristics are why stem cell research holds such great promise for the treatment of life-threatening and debilitating diseases such as Alzheimer's disease, cancer, Parkinson's disease, and juvenile diabetes. Understanding what the genetic and biochemical signs are that trigger stem cell differentiation may allow researchers to one day program new cells to repair damaged tissues and organs, and to better understand disease processes. Here is a current list of the sources of stem cells:
- Embryonic stem cells - They are harvested from the inner cell mass of the blastocyst seven to ten days after fertilization.
- Fetal stem cells - These cells are taken from the germline tissues that will make up the gonads of aborted fetuses.
- Umbilical cord stem cells - Umbilical cord blood contains stem cells similar to those found in bone marrow.
- Placenta derived stem cells - Up to ten times as many stem cells can be harvested from a placenta as from cord blood.
- Adult stem cells - Many adult tissues contain stem cells that can be isolated. The goals of stem cell research include curing diseases, cloning, and gene-line engineering. Cloning is directed towards making duplicate animals or humans. Gene-line engineering is directed toward permanent change in disease resistance and aesthetic and functional enhancements.
What is a unique property of stem cells is that they?
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; and
- what 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.
A brain stem cell only produces its own type of cell which type a stem cell is this brain stem cell?
Unipotent
What type of stem is present in trees?
Are you talking about the sex organs in a plant? If so the two types are the pistil (female reproductive organ) and the stamen (male reproductive organ). Most plants contain both as plants reproduce using pollination, a movement of pollen (from the stamen) to the pistil. This is how flowers are germinated. Hopefully this solved the question. Helped by a sophmore in highschool
What kind of cells can stem cells become?
Stem cells can become any cells. Stem cells are generated right after the formation of a newly fertilized egg. They are present in both adult and embryonic body.
How are stem cells trnsplanted?
Stem cells are cells that have not specialised. Specialist cells can only be the one thing that they are specialised for; ie, you cannot turn skin cells into a heart, or liver cells into a brain. Stem cells have not specialised and can therefore become any type of cell. I am not sure how they are stimulated to become one kind or another, but they can. Adult stem cells are not as good as embryonic stem cells, but because harvesting embryonic stem cells requires the destruction of a human embryo it is banned in many countries.
What do scientists hope to accomplish through stem cell research?
That is an unbelievably loaded question! I can answer from my perspective. Plant Stem Cells could very well be the next medical evolution in the US. They are proving to be the perfect synergy between traditional medicine and the "natural/organic" trend that people are moving towards. In short. Plant Stems Cells have the uncanny ability to actually specialize within the human body. This means that stem cells from certain plants can actually help with cells that regulate the immunity, or they can detoxify and rejuvenate kidney, liver, lung and even brain issue. The trick is know which plant stem cells work best with which systems or tissues in the body. Then knowing the chemical makeup in the plants to help balance body chemistry to optimize the running of the entire body. In terms of healthcare treatments and preventative health. Plant Stem Cells are the next generation of drugs used to treat some of the most common ailments along with some of the most devastating diseases we are currently facing. You can visit our website www.plantstemcells.net If you are a healthcare professional you can also get access to our research tools and only education forums. www.plantstemcells.net for more information
What are the differences between T cell and stem cell?
Stem cells are undifferentiated biological cells that can differentiate into specialized cells and can divide (through mitosis) to produce more stem cells. So, they basically have the ability to grow any type of cell.
T cells or T lymphocytes are a type of white blood cell that plays a central role in the immune system. So, they basically help us resist disease.
Why are embryonic stem cells more useful than adult stem cells?
All cells consist of a nucleus, all nucleus consist of 23 pairs of chromosomes and all chormosomes consist of many genes. Each of these gene carries a specific template to make specific proteins. These proteins are responsible for carring out many functions throughout your body.
As of right now you are composed of many, many cells. Each and everyone of the cells is structurally the same, but each one encodes different protiens. liver cells are responsible for encoding proteins important to liver functions and heart cells are important to make proteins important to heart function. It is also important to realize that just because a heart and a liver look different does not mean their cells look any different. it is the arrangement of those cells and that make them look different not the cells themselves.
Now when you were first created you were one cell(called a zygote). This one cell was excatly like every cell you have in your body right now, except for one difference it had not limitations. it had the ability to encode any protein, it had the POTENTIAL to become anythining. After several cell divisions some cells became fated, meaning some of their genes were turned off so they could only make certain proteins. Ie, certain cells were fated to become heart cells so all the genes unrelated to heart functions were turned off.
To this day we still do not know how out genes turn on and turn off, but if were ever were able to figure it out we could solve each and every disease out there. it is the most important next step science has to take.
But to answer your question, embryonic stem cells are "better" because none of their genes are turned off so they can become any type of cell and encode every protein, while adult stem cells are much more limited.
Does organelles allow eukaryotic cells to carry out more functions than prokaryotic cells?
Yes, the amount of organelles will differ in cells depending on their function. For example, muscle cells will have more mitochondria to provide more energy. Some organelles will just be larger; for example, the smooth ER is responsible for detoxification. There will only be one smooth ER unit in every cell, but cells involved in detox like liver cells will have a larger smooth ER.
What are two ethical problems with stem cell research?
This is not a question that can be answered with a simple 'yes' or 'no'. Embryonic stem cell research has the potential to cure a range of degenerative disorders from Alzheimer's to ALS, as well as supply organ transplants without the risk of immune rejection. To harvest functional stem cells, they must be extracted from a fertilized egg before the cells differentiate, or 12-14 days maximum. Fertilized eggs from in vitro fertilization clinics have been used only after fertilization attempts have ended. These fertilized eggs are notguaranteed to implant or be able to develop into a baby, and neither of these if a prerequisite for harvesting ES cells. Only 24% of attempted IVF pregnancies yielded a live and healthy baby in 2005 (mdwebsite.com). On the one hand, these fertilized eggs will never be used for anything yet hold such a promising therapy for so many individuals alive today. The ethical parallel for this situation is, "is it ethically wrong to use functional organs as transplants from a deceased individual, or wouldn't it be a waste?" On the other hand, we realize that society has created these fertilized eggs, and a small percentage of them have the potential to develop into healthy babies if given to correct situation. ES harvesting as of yet, does not differentiate between these two, and must destroy the embryo in order to retrieve the ES cells. This is destroying the potentialfor life in certain embryos. Though they are not alive yet, they do contain the ability to develop into an organism, a human, and they were intentionally created to do just that. In regards to were the promise and statistics lie, it seems unethical to allow an intentionally manufactured collection of multipotent cells to go to waste when so many people in pain and nearing pre-mature death could benefit from them.
This is true but one fact always seems to be overloooked. An embryo is not the only place that stem cells can be taken from. Umbilical cord stem cells have the capability of changing into almost just as many cells as embryonic stem cells. Just a few weeks ago an autstic boy was cured with umbilical cord stem cells.
What kind of stem cells can develop into any kind of cells in the human body?
Cells up to 8 cell stage in human embryo can develop in any kind of cell in body. Inner cell mass in blastocyst can develop into any kind of cell in human body.
