Biotechnology
1) All living organisms contain DNA as their hereditary material.
2) DNA does the same two jobs in all organisms, heredity and code for proteins.
3) The process of coding for proteins is the same in all organisms.
4) Different species share some genes in common and some that are different.
5) It is possible for a gene to be taken from an individual of one species and inserted into an individual of a different
species.
6) If that gene goes through protein synthesis, then the organism will be able to make a new protein that it didn’t have
before.
7) Scientists have taken the gene from a firefly that makes it luminescent and inserted that gene into other species such
as tobacco plants.
8) Isolating a gene from a species involves a set of tools and techniques.
9) DNA Polymerase is used copy DNA molecules.
10) RNA Polymerase is used to copy RNA molecules from a DNA template.
11) A restriction enzyme, found in bacteria, cuts up DNA molecules at specific base sequences.
12) DNA ligase glues DNA strands together.
13) Polymerase Chain Reaction is used to copy DNA molecules millions of times.
14) Gel Electrophoresis is used to separate molecules by size and charge.
15) These tools and techniques are combined to carry out the most common applications of Biotechnology.
16) A gene can be taken from a human and put into a bacterium.
17) The bacterium can then produce the human protein.
18) This is called genetic engineering.
19) For diabetics, bacteria are used to produce insulin.
20) Moving a gene from one organism to another requires finding the gene in the first place.
21) Once it is isolated, the gene is put into a short segment of DNA called a plasmid that bacteria will pick up from the
environment.
22) Bacteria take up DNA from the environment in a process called transformation.
23) The transformed bacteria will start producing the protein of interest.
24) Culturing the bacteria and giving them ideal growing conditions will result in lots of the protein being produced.
25) Some scientists use Biotechnology to clone organisms.
26) To clone a mammal, an egg cell has its nucleus removed using a small syringe.
27) A body cell, such as a skin cell, from another organism has its nucleus removed.
28) The nucleus from the skin cell is inserted into the egg cell.
29) The egg cell now is exposed to a low voltage of electricity and some proteins involved in development of the embryo.
30) After the newly cloned embryo has formed into a blastula, it can be implanted into the uterus of a host female, usually
of the same species as the donor egg.
31) Cloning of many animals has been done successfully, but the process has had a low rate of success.
32) Some scientists want to clone humans, but international law has so far prevented this from occurring.
33) DNA fingerprinting can be used to identify any human from any other human.
34) Scientists take a sample of DNA and use restriction enzymes to cut up DNA into smaller pieces.
35) Because of mutations, each person’s DNA will be cut up into many different size pieces.
36) Scientists take the pieces of DNA and put them into a gel electrophoresis chamber.
37) The pieces separate out by size and produce a pattern of sizes that is unique to each individual.
38) Since the gel is not stable, scientists have to take the DNA out of the gel and get it onto a more permanent medium.
39) The most common technique is called the Southern Blot. The DNA is squeezed from the gel onto filter paper and then
the filter paper is X-rayed to form a permanent image that can be used in court.
40) Forensic scientists use DNA fingerprinting to tell whether or not a suspect was at the scene of a crime.
41) DNA fingerprinting is not usually enough evidence to convict a person of a crime, but some kinds ofcrime, such as
rape, it is very strong evidence.
42) Some scientists want to identify the genes that cause diseases in humans and replace the defective gene with a
normal functioning gene.
43) This technique is called gene therapy.
44) Some people have a disorder called sickle cell anemia.
45) These people have blood cells that change shape (sickle) when they experience low oxygen conditions.
46) This occurs because of a mutation in a gene that causes the hemoglobin protein to change shape and when it
changes shape, the blood cell also changes shape.
47) In gene therapy, a virus would be modified to carry a copy of the normal gene for the hemoglobin protein.
48) This protein would infect cells that produce the protein and insert a copy of the normal gene into the chromosomes of
the cell.
49) The more cells that were infected, the more chances that a cell would produce the normal hemoglobin protein.
50) This technique has not had very much success yet, but scientists are still working to make it more effective.
51) Modifying bacteria to make a critical protein does not create any ethical dilemmas for most people, but other aspects
of biotechnology do create ethical dilemmas.
52) An ethical dilemma occurs when a decision has no clear-cut right or wrong answer.
53) For example, undergoing an experimental gene therapy program to cure a disease might kill the person.
54) The risk of undergoing the procedure might be greater than the benefit, but some people may choose to do it and
other may choose not to do it.
55) As our capabilities for modifying the genetic makeup of organisms improves, the number of ethical dilemmas
increases.
56) Most people when asked, will say that it is OK to clone any other organism except for humans.
57) So while cloning is generally supported, human cloning is banned.
58) Many scientists want to produce human stem cells that have the capability to replace diseased tissue in humans.
59) Stem cells can come from adults or embryos.
60) Adult stem cells are thought to be less able to become other kinds of cells and have a limited life span.
61) Embryonic stem cells are harvested from discarded embryos, but show greater potential and a longer life.
62) Many people say that life begins at conception, the point at which the sperm fertilizes the egg.
63) For these people, destruction of the embryo to get the stem cells is morally wrong.
64) Other people say that life begins at some point after conception.
65) For these people, destruction of the embryo, which is only potential life, is less important than the value these cells will
have to relieve the pain and suffering of people who are already living.
66) Deciding where you stand on this issue helps you understand the concept of an ethical dilemma.
67) When making a choice, you want to avoid what is called “the slippery slope.”
68) A slippery slope occurs when you say that something is wrong for one group, but not wrong for someone else.