In today's class we started a new topic, stem cells, controversial theme now days and many arguments that may be analysed. The activity is to answer some questions to the videos watched in class.
The Embryo Takes Shape
link to the video here -->
http://www.teachersdomain.org/resource/tdc02.sci.life.cell.embryoshape/
- What directs the sequence of events that turn a blob of cells into an embryo with specialized tissues and organs?
- The narrator says that “cells talk to each other.” What does that mean?
- How do cells in different parts of the embryo become different kinds of cells and organs?
- What kinds of proteins are found in different cells and organs?
- What tells the cells which kinds of proteins to make?
- What is the relationship between DNA, genes, and the proteins that are produced in cells?
1.- The sequence that change a blob of cells into a embryo is called gastrulation.
2.- The cells don't really communicate with each other, what happens it that they use chemicals messages that trigger reactions in other cells that spread up .
3.- When the cells send their chemical message different groups of genes are turned on and they become specialized in one thing.
4.- We can find collagen, that is the protein of the skin, tendons and the bones, keratin, the protein of the hair, crystalin, which makes the lens of the eyes clear, actin and myosin, which moves muscles and fibres, hemoglobin, that carries the oxygen of the lunghs to the rest of the body through the blood.
5.- Chemicall messages tell the cell which part of the body they'll be part of.
6.- Proteins are created when a special gene identifies the DNA and turns on the correct gene.
Genetic Tool Kit
link to video here -->
http://www.teachersdomain.org/resource/tdc02.sci.life.gen.genetictoolkit/
- How has evolution tinkered with genes of animals?
- What role has embryos played in the study of evolution?
- What did the experiment with fruit flies and mice show?
- What does the presence packages of information suggest about evolution?
1.- The evolution has "mixed" genes, I mean, it created new combinations of genes to create different species.
2.- The embryos develope very fast and they are very easy to study during their growing process. Compare species and learn more about the growing phases.
3.- The experiment has shown as that there are genes that are repited in the living beings, like ancestors, identical in every specie, and there are other factors that create the differences in the species.
4.- It proves that there are identical genes that help every organism to develope and function correctly and those genes are active in the animals.
Stem cells Debate
- Why are stem cells considered so valuable for medical research?
- Why did the researchers have to narrow the spectrum of genes within stem cells? (video 1)
- What are the sources of stem cells and the advantages and disadvantages associated with using each?
- What are the three cases presented at the beginning of the second video?
- How might a stem cell be used to treat spinal cord injuries?
- Explain the outcome of the experiment with injured rats presented in the second video?
- What issues surround the debate over of stem cell research?
- What issue do you think needs to be debated as we make decisions about stem cell research?
1.- Because stem cells can become any other cell of the body, and it has an important medical use, being able to cure many diseases we yet can't.
2.- At the beggining there were 20.000 genes from which he had to find which of them trigered the cell to become a stem cell.
3.- Stem cells can be harvested from a embryo, it has many medical uses and there's still many research remaining. But there's an ethical controversy. When harvesting the stem cells, the embryo is destroyed, many people is against this practice because it attempts against life, or a future life.
4.- An ice-hockey player with an injury in his spinal cord, two cousins with a metabolic disorder that causes brain cells to die, called Toy-Sachs disease, and a boy with diabethes.
5.-The cientist used a rat as a first attempt of healing a spinal cord injury. They put a "bridge" with stem cells in it. The bridge would give enough time to the stem cells to specialize to the place they belong and finally fix the separation within some months/years.
6.- Wether we can attempt against life or is there another way to harvest stem cells. If we don't use the stem cells in the future ¿ Is that interfiering with scientist research?
