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Stages of human development infancy
Advantages and disadvantages of stem cell research
What are the advantages and disadvantages of stem cell research
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Recommended: Stages of human development infancy
What is a stem cell?
Stem cells have the ability to divide for indefinite periods in culture and to give rise to specialized cells. They are best described in the context of normal human development. Human development begins when a sperm fertilizes an egg and creates a single cell that has the potential to form an entire organism. This fertilized egg is totipotent, meaning that its potential is total. In the first hours after fertilization, this cell divides into identical totipotent cells. This means that either one of these cells, if placed into a woman's uterus, has the potential to develop into a fetus. In fact, identical twins develop when two totipotent cells separate and develop into two individual, genetically identical human beings. About four days after fertilization and after several cycles of cell division, these totipotent cells begin to specialize, forming a hollow sphere of cells, called a blastocyst. The blastocyst has an outer layer of cells and inside the hollow sphere, there is a cluster of cells called the inner cell mass.
The outer layer of cells will go on to form the placenta and other supporting tissues needed for fetal development in the uterus. The inner cell mass cells will go on to form virtually all of the tissues of the human body. Although the inner cell mass cells can form virtually every type of cell found in the human body, they cannot form an organism because they are unable to give rise to the placenta and supporting tissues necessary for development in the human uterus. These inner cell mass cells are pluripotent — they can give rise to many types of cells but not all types of cells necessary for fetal development. Because their potential is not total, they are not totipotent and they are not embryos. In fact, if an inner cell mass cell were placed into a woman's uterus, it would not develop into a fetus.
The pluripotent stem cells undergo further specialization into stem cells that are committed to give rise to cells that have a particular function. Examples of this include blood stem cells which give rise to red blood cells, white blood cells and platelets; and skin stem cells that give rise to the various types of skin cells. These more specialized stem cells are called multipotent.
While stem c...
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...homson
2. Dr. Gearhart
D. The potential uses of pluripotent stem cells.
1. Better understand human development
2. Testing of experimental drugs
3. Cell Therapies
4. Problems
a.) understanding the basics………
b.) immune system
c.) rejection
E. Adult stem cells.
1.) Myth vs. Fact
F. Some adult stem cells have the same potential as pluripotent stem cells.
1.) Committed, or not?
G. What is wrong with using adult stem cells.
1.) pluripotent stems cells do not exist in adult humans
2.) There are no stem cells for all tissue types in adult humans
3.) An abundance of totipotent cells do not exist in adult humans
4.) IT TAKES TIME TO GROW!
H. Conclusion.
The final genre of stem cells is that of multipotent stem cells. These cells are more specialized than the other two categories and thus are more restricted in their capability. Multipotent stem cells are derived from pluripotent stem cells.
Stem cells are pluripotent cells of the body which are “undifferentiated.” This means that stem cells can ultimately give rise to any type of body tissue. Thus stem cells have the potential to cure a vast number of diseases and physical ailments including Parkinson’s, diabetes, spinal cord injury, and heart disease. Consequently, stem cell research and the development of associated medical applications are of great interest to the scientific and medical community. The area of stem cell research involving human embryonic stem cells is of particular interest in that embryonic stem cells are derived from week-old blastocysts developed from in vitro fertilized eggs. As opposed to adult stem cells, which must undergo a complicated process of de-differen...
Stems cells are immature cells found in embryos that can develop into any kind of specialized cells. They can form virtually any cell of the human body. These types of stem cells are known as pluripotent cells. Multipotent cells are stem cells that are more mature; they can be found in adults and children. Multipotent cells are not as flexible as pluripotent cells, as they have already developed into more specialized human cells.
Stem cell research began in 1956 when Dr. E Donnall Thomas performed the first bone marrow transplant (“Adult stem cells are not more promising,” 2007). Since that time, research has evolved into obtaining cells from a variety of tissues. According to stem cell research professors, Ariff Bongso and Eng Hin Lee (2005), “Stem cells are unspecialized cells in the human body that are capable of becoming cells, each with new specialized functions” (p. 2). Stem cells are in various adult tissues, such as bone marrow, the liver, the epidermis layer of skin, the central nervous system, and eyes. They are also in other sources, such as fetuses, umbilical cords, placentas, embryos, and induced pluripotent stem cells (iPSCs), which are cells from adult tissues that have been reprogrammed to pluripotency. Most stem cells offer multipotent cells, which are sparse...
There are three types of stem cells. Embryonic stem cells which are taken from a fertilized egg, somatic stem cells are fully matured cells taken from an adult, and the more recently founded pluripotent stem cells which are those that can be induced through experimentation to take on specific functions (NIH, 2013).
Embryonic stem cells are derived from a four or five day old human embryo that is in the blastocyst phase of development (see figure 5). The embryo’s that are used for stem cell research, are extra’s that have been created in IVF clinics (in vitro fertilization), that are no longer needed. Embryonic stem cells are totipotent (cells with the potential to develop into any cells in the body). Scientists have discovered an alternative to embryonic stem cells, these cells ...
Stem cells are mother cells that have potential to develop into a new different cell in the body. It can self-renew or multiply while developing into other types of cells, for example they can become cells of the blood, heart, bones, skin, muscles and brain. Stem cells were discovered in human cord blood in 1978, and in 1998, Thompson, from the University of Wisconsin, isolated cells from the inner cell mass of early embryos (early stage of an animal or person before it is born) and developed t...
There are many different types of stem cells that are being looked at for research. These include embryonic stem cells, adult stem cells, and induced pluripotent cells. Embryonic stem cells are cells that have the potential to produce many different cells in the body. They are cells that are tak...
Stem cell research is on the forefront of regenerative medicine and biological science. It is the study of certain cells in the inner mass of the embryo that are produced a few days after the embryo forms during the blastocyst stage. They are the most primitive of all human cells. They are undifferentiated cells, which mean the cells are not designated to be any special type of cell, such as a nerve, muscle, or skin cell. The cell's specialization is later influenced by the molecules, which are usually proteins that surround the cell (Marshak 220-223). The proteins are typically produced by the mother, but under certain laboratory conditions, distinctive proteins can be introduced and a definite, mature cell type is produced. The cells that are produced could be implanted into a subject to replace worn out cells, or cells that have been destroyed due to disease or injury.
You begin life as a single cell, formed when the sperm fertilises the egg. Out of all the sperm it only takes one sperm and one egg to fertilise at conception. This is called fertilization; which takes place in the Fallopian tube, the fertilized egg then divides
As the research teams of the EuroStemCell project teach in their educational short film A Stem Cell Story, there are certain stages of development while in the uterus where most of our cells stop dividing and stabilize into a specific kind of cell. They do not mutate throughout our life. These cells are referred to as specialized cells. Once they are damaged or die they cannot regenerate themselves.
To get an idea exactly what embryonic cells are, it is necessary to understand fully how they’re retrieved and composed of. Embryonic stem cells come from eggs that have been fertilized by in vitro, which is an artificial environment outside the living organism such as a test tube. When fertilization is successful, the sperm head carrying the nucleus enters the egg. The egg dives first into two cells, then into four. With more divisions, a multicellular ball of cells known as a blastocyst is formed. Inside the blastocyst is a hollow ball which includes the embryonic stem cells which can be retrieved with a pipette, a small glass tube used to transport a measured volume of liquid, and transferred to a dish. Under certain conditions, the embryonic...
Stem cells are located deep down in our bone marrow. They have the incredible ability of “generating an endless supply of red cells, white cells, and platelets”(1). They have been called the “Mother of all blood cells” due to their ability to regenerate the entire blood supply of a persons body. Just to think that this is possible is actually pretty incredible. The man who claims to be responsible for the discovery of this gem is a immunologist from Stanford University named Irving Weissman, and his collaborators at SyStemix, (a biotech company that he cofounded in 1988, located in Palo Alto, CA). He and his company are so confident about these cells, not only have they obtained a government patent on the process by which these specific cells are separated from other cells, they have also patented the cells themselves. They have even convinced Sandoz Ltd. (a giant Swiss drug-and-chemical company) to purchase 60 percent of the stock for SyStemix for a reported 392 million dollars.
The female reproductive systems is made of 9 parts. The sex cell for the female reproductive system is called the egg or ovum. The egg spends it’s dormant life in the ovaries until it is released. The egg has 23 chromosomes within it. The ovaries have two goals: to create and house eggs and the release the female sex hormones, estrogen and progesterone. The fallopian tubes are what the egg travels through to reach the uterus. Fallopian tubes contain tiny hair-like structures called cilia; the cilia allows for mobility of the egg. The fallopian tube is roughly the size of 2 hairs, and is the site of where ectopic pregnancies happen. The process of the egg getting released from the ovaries through the fallopian tubes is called ovulation. Ovulation happens on the 14th day of the menstruation cycle The uterus is where the egg goes to after it travels through the fallopian tubes. The developing baby is held and nourished in the uterus. When the uterus is empty, it’s roughly the size of a fist but expands one an embryo starts to develop. The endometrium is the lining of the uterine wall. It’s used to protect the fetus. When the egg isn’t fertilized, menstruation ha...
Sally: Embryonic cells are "undifferentiated." Undifferentiated cells have not gone through changes that make some cells into skin cells or muscle cells or brain cells, for example. Undifferentiated cells can become any cell in the body because it can activate any gene on any chromosome, but as cells develop, the DNA of certain cells fold in particular ways making large portions of the DNA inaccessible. This makes sure that the wrong genes do not get turned on at the wrong time or in the wrong place.