4.4.1 Outline the use of polymerase chain reaction (PCR) to copy and amplify minute quantities of DNA.
Polymerase chain reaction is the amplification of DNA. Temperature of 95C is used instead of enzyme. DNA polymerase (taq polymerase) is added to protect DNA against reaction temperature. DNA strand separates, primer is added and reaction starts. PCR helps forensics experts or researcher to obtain large amount of DNA copies in a few hours.
4.4.2 State that in gel electrophoresis, fragments of DNA move in an electric field and are separated according to their size.
in gel electrophoresis, fragments of DNA move in an electric field and are separated according to their size.
4.4.3 State that gel electrophoresis of DNA is used in DNA profiling
Gel electrophoresis of DNA is used in DNA profiling.
4.4.4 Describe the application of DNA profiling to determine paternity and also in forensic investigations.
Forensics use collects samples containing DNA to identity paternity, samples such as: fingerprint, blood, semen. Polymerase chain reaction might be use to amplify DNA, gel electrophoresis as well.
4.4.5 Analyze DNA profiles to draw conclusions about paternity or forensic investigations
outcome of DNA profiling: knowledge of the number of human genes. discovery of proteins and their functions. Evolutionary relationship between taxa
4.4.6 Outline three outcomes of the sequencing of the complete human genome found by The Human Genome Project (1990)
number of genome: 25,000. Huge improvement in sequencing technology. new insight into role of non coding DNA. medical benefits; diagnosis of disease, identification of disease carriers, better drug designs knowing protein structure
4.4.7 When genes are transfered between species, the amino acid sequence of polypeptide translated from them is unchanged because the genetic code is universal
When genes are transfered between species, the amino acid sequence of polypeptides translated from them is unchanged because the genetic code is universal.
4.4.8 Outline a basic technique used for gene transfer involving
A plasmid is removed from host cell, cut open by restriction enzyme, endonucleases. The gene to be copied is placed inside the open plasmid using DNA ligase (gene splicing). The plasmid is now called recombinant plasmid and can be used as a vector. Vector is placed inside the host bacterium. Bacterium is put in an ideal condition, into a bioreactor containing nutritious liquid at warm temperature to grow and proliferate. The bacterium mostly used is E.Coli.
4.4.9 State two examples of the current uses of genetically modified crops or animals
genetically modified tomatoes: flavr savr tomatoes are modified to delay ripening and rotting process, other tomatoes are modified to tolerate high salt content in soil. Transgenic sheep produce milk with factor IX for people with hemophilia.
4.4.10 Discuss the potential benefits of one example of genetic modification
help farmers by improving food production, produce own pest control that are better for environment with less chemical involved. produce protein for medication. farmers have more control of what they produce. reduce famine by pest resistant or less water required crops.
4.4.10 Discuss harmful effects of one example of genetic modification
no one knows the long term effect of GM food. unnatural advantages over species, taking over the habitat. more risk for allergies. large portion of food supply belong to one corporation. decrease in biodiversity
4.4.11 Define clone
a group of genetically identical organism; or a group of cells artificially developed from single parent.
4.4.12 Outline a technique for cloning using differentiated cells
Somatic cell (non gamete) from udder of original donor sheep is collected and cultured. the nucleus is removed. nucleus of an unfertilized egg collected from another sheep is also removed. Using electrical current, the egg cell and the nucleus from the somatic cell are fused together. the new cell is developed in vitro similar to a zygote and start to form an embryo. The embryo is placed and develops in the womb of a surrogate sheep.
4.4.13. Discuss the ethical issues of cloning in humans
Using stem cells, it is made possible to grow skin to repair serious burn. grown heart muscle to repair a failing heart. growing kidney tissue to repair a failing kidney.