Monday 28 February 2011

The science of addiction

Drugs have a severe impact on the brain and body of the user. Even mild substances like alcohol can have major effects on a human body over time. The aging process can be speed up by the use of drugs, which can bring with it increased chances of life threatening diseases such as cancer. Now you might think that this isn't so bad, that it would be easy to give up drugs, that one little try won't hurt. Anyone who thinks that is, sadly wrong. Addiction is a powerful force. You see the brain has a natural reward system, when you eat or drink you experience a relative high, and are compelled to do so again. This is caused by neurotransmitters which are natural parts of the brain. Drugs stimulate these neurotransmitters into producing an unnatural high. This process induces addiction. Once you've had a taste of the extreme highs cause by drugs such as Cocaine or Marijuana, it is difficult to go back to the natural highs induced by everyday life. Many of these drugs not only cause a dependency, they also have other negative effects on the body such as decreases in brain activity, and dulling of reflexes. All in all it is best to stay away from drugs, alcohol, and cigarettes. Weather they're legal or illegal, they all have negative effects on the body and mind of the people who use them.

Tuesday 4 January 2011

Questions for Cloning

1. Who is Dolly? Dolly is the first mammal ever to be successfully cloned.

2. When a zygote divides into to separate cells, it is called: A Somatic cell

3. Somatic cells are also called diploids.

4. In order to clone a gene, a gene is inserted into a plasmid.

5. In order to create an embryo from a somatic cell, the donor egg cell must have its nucleus removed.

6. List all the materials needed to clone a mouse.

Microscope, Petri dishes, Sharp pipette, Blunt pipette, Cell division stimulant.

7. Place the following steps in the correct order.

#4 Stimulate cell division
#6 Deliver baby
#2 Remove and discard the nucleus from the egg cell
#1 Isolate donor cells from egg donor and germ cell donor
#3 Transfer the somatic cell nucleus into the egg cell
#6 Implant embryo into a surrogate mother

8. There are two time gaps in the process of cloning. What are they?

First you must wait for the DNA to be reprogramed, then you must wait for the cell to divid at least 16 times (this is after you have added the stimulant).

9. What color will the cloned mouse be? Brown.

What is the name of this mouse? Mini-mimi

10. Why is cloning extinct animals problematic? Because it is difficult (if not impossible) to find properly preservered Dna from most extinct animals.

11. What are some reasons a person might want to clone a human?

To help infertile couples have children or to replace a deceased child

The Clone Zone

12. What animal was cloned in 1885? A Sea urchin.

13. How did Spemann separate the two cells of the embryo of a salamander in 1902? Using a noose made of hair.

14. The process of removing a nucleus is called enucleation.

15. In 1952, the nucleus of a tadpole embryo cell was placed into a donor cell. Did it work to clone the animal? Some what but the clones grew abnormally.

16. Can the nucleus of an adult cell be injected into an egg cell and produce a clone? Yes

17. Why are mammals hard to clone? Mammals have very complex DNA structors.

18. What were the names of the first two cloned cows? Fusion and copy

19. In what year was the National Bioethics Advisory Council formed? It was formed in 1990

20. The first mammal clone to be produced from an adult (somatic) cell? Dolly

21. What do scientists do to adult cells to make them "behave" like embryos? By using an electric shock.

22. Transgenic, cloned sheep were used to produce what medical protein? The IX protein.

23. What is a stem cell? A cell who's job in the body which has yet to be determined.

24. Briefly describe in your own words, why CC the cat was not identical in color to Rainbow, even though she was a clone. Because she had different color genes switched on then Rainbow

25. What is "nature vs nurture"?

It is the ongoing debate about what determines a persons personality: The way that they were raised, or their predetermined genome.

26. For each of the following scenarios, indicate YES (it is cloning) or NO (it is not cloning)

No Sperm taken from a mole goat is combined with a female's egg in a petri dish. The resulting embryo is implanted into the female's uterus to develop
Yes sheep embryo, composed of 16 cells, is removed from the mother's uterus and separated into indivudal cells. Each cell is allowed to multiply, creating 16 separate embryos, which are then implanted in different female sheep to develop to maturity.
No A cow with many desirable traits is stimulated with hormones to produce a number of egg cells. Each of these eggs is fertilized and implanted into a surrogate mother.
No In vitro fertilization
Yes Cell nuclei from an extinct wolly mammoth are placed into enucleated cow cells.

27. Define or describe each of the following processes (you may need to reset the Cloning or Not Screen)

In vitro fertilization is a process by which egg cells are fertilized by sperm outside the body

Embryo splitting is the process of splitting an embryo in to 2 to 8 cells which will then develop in to separate embryos.

Somatic Cell Nuclear Transfer is a method for creating a clonal embryo, by using an ovum and a donor nucleus.

Multiple Ovulation Embryo Transfer is where the multiple ovulation is where the female animal is manipulated hormonally to produce more than the usual number of eggs during ovulation. Then after each of the eggs is fertalized they are transplanted in to another separate mother, where they are allowed to grow.

Artificial Insemination is the process by which sperm is placed into the reproductive tract of a female for the purpose of impregnating the female by using means other than sexual intercourse.

28. What is one reason why cloning animals has such a high failure rate?

An egg with a newly transferred nucleus may not begin to divide or develop properly

29. What is a telomere and how does it affect cloned animals?

A telomere is the DNA sequence at the end of the chromosome that gets shorter every time a cell is copied

What Are Some Issues in Cloning?

30. Pick one of the questions to ponder and ....ponder it. Write a brief essay on your thoughts and opinions.

What Are Some Issues in Cloning?

First of all cloning has a bad reputation which in and of its self is a bad thing for any new technology, (no mater why it has that reputation). Above all cloning must be the kind of research that organizations want to fund, with out funding, no progress can be made. Beside that cloning is very expensive, not a lot of research foundations can afford to try and clone something. This is because of the high failure rate of 0.1 chance of success. All of these things play in to the reason why cloning can be unconventional, but cloning also has many upsides.

Monday 3 January 2011

1. What is a GM Crop.
It is a Crop that has been purposefully and genetically modified by humans for our benefits. An example of a genetically engineered crop is a tomato that has been redesigned to last longer after it has been picked.

2. List 2 arguments FOR the growing of GM crops
Having pest resistant crops could help the environment because
pest resistant crops require much less pesticide and, therefor much less chemicals. Technically Genetically modifying plants is natural. Plants modify themselves through evolution and humans have always used selective breeding to change plants and animals.

3. List 2 arguments AGAINST the growing of GM crops.
It is posible that GM crops can cause allergies. In the process of making GM foods genes that cause allergens can become mixed. This puts the health of many children and adults at risk. GM crops are expensive to grow and not all farms can afford them. The GM crops domination of the market would put the 'Ma and Pa' farms at risk of going out of business. This in turn could hurt the economy.

4. Practice this simulation until you get the largest ears of corn. How many times did it take you?
It took me only 2 tries to get the largest possible corn.

5. List two foods and describe how they are being modified
Bananas are being modified so as to work as a vaccine for a number of diseases.
Many fruits such as strawberries melons and even grapefruits. These can be modified for a number of things such as: flavor shelf life and resistance to bugs.

Do you think food should be labeled if it has been genetically modified? Why or Why not?
I definitively think that food should be labeled if it is modified. I have nothing against genetic engineering, I believe it is a fantastic new technology that has the potential to benefit man kind, but many people fear genetic engineering. These people may not always be correct in their fear but they at least deserve to know what they are consuming and they deserve to make their own decisions about whether or not to eat genetically engineered products.

Monday 13 December 2010

Mitosis tutorial questions

1. a. Prophase
b. Metaphase
c. Interphase
d. Prometaphase
e. Cytokinesis
f. Telophase

2. a. 46
b. 46
c. Centrioles
d. They divide

3. a. Metaphase
b. Telophase
c. Prophase