MODULE 6 IQ2: Biotechnology Flashcards
biotechnology meaning
use of living organisms, biological processes or biological products to create new products that are useful to humans
types of past biotechnology
selective breeding, fermentation, ancient antibiotics
what is selective breeding
choosing particular desirable characteristics and breeding individuals that possess these traits together to produce offspring that exhibit favourable characteristics
example 1 of selective breeding
wheat –> einkorn (T. boeoticum) and goat grass (A. speltoides)
- einkorn was cross-pollinated with goat grass to produce emmer (Triticum dicoccoides)
- this was cross bred with another goat grass (A. squarrosa) to produce durum/pasta wheat
- the durum species was re-crossed with parents to give rise to modern wheat
benefits of selectively bred wheat
- larger seeds –> increased grain yield
- non-shattering rachis
- loss of seed dormancy
- improves disease resistance
example 2 of selective breeding
cow –> selected on the criteria of:
- reasonable rapid growth rate
flexible diet
- no adversion to breeding in captivity
- relatively pleasant disposition
- modifiable social heirarchy
downsides of selectively bred cow
- decrease in animal welfare
- decrease in genetic variation and biodiversity
- gene linkage of negative traits with positive traits
what is fermentation
process that converts sugars into energy. generally processed via glucose –> ethanol + carbon dioxide
example of fermentation
yoghurt
- lactose is broken down into glucose and galactose
- glucose is broken down to lactic acid
what is ancient antibiotics
form of treatment that is used to treat bacterial infections
- mouldy bread or honey used by Egyptians
- 600 BC mouldy soybean curds used to treat boils in China
DNA insertion methods
microinjection, Ti plasmid insertion, gene gun
microinjection process
- fine glass needle to insert foreign gene into nuclei of host organism during embryonic state
- offspring of these embryos contain genes from other species and is therefore transgenic
Ti plasmid insertion process
bacterium agobacterium temefaciens –> causes development of disease crown gall in plants by inserting own DNA into hosts DNA
- splices foreign gene of interest into plasmid of bacterium
- bacteria is now vector for host plant
- mainly used to create BT cotton
gene gun process
- metal atoms (usually tungsten particles) fired at high rate via gene gun
- fired at nuclei of plant cells
transgenic organisms
organism that has received gene from another species, usually via the process of recombinant DNA
example 1 of transgenic organism
BT cotton
- contain 1 or more foreign genes derived from soil-dwelling bacterium –> produced crystal insecticidal proteins (Cry proteins) effective in killing caterpillar pests
example 2 of transgenic organism
golden rice
- biosynthesis of beta-carotene, precursor of vitamin A, in edible parts of rice
present biotechnology
artificial insemination, artificial fertilisation, polymerase chain reaction, recombinant DNA technology
future biotechnology
gene therapy, pharmacogenomics, CRISPR-Cas9
gene therapy process
if a specific gene is identified for a genetic disease, gene therapy will be used to:
- inactivate or knock out defective gene completely
- deliver new gene to help fight disease
- repair abnormal genes
- control expression of particular gene
pharmacogenomics process
- sequencing of patient’s relevant genes to identify SNPs
- by comparing with known SNPs, optimal choice of drugs can be made
main goal: - prediction of patient’s response to drug
- improved drug discovery
genome editing meaning
group of technologies that give scientists the ability to change organism’s DNA
CRISPR-Cas9 process
- when infected with virus, bacteria capture small pieces of virus’ DNA and inserts into own DNA
- forms CRISPR arrays –> allows bacteria to remember virus
- when virus attacks again, bacteria produces RNA segments from CRISPR arrays that recognise and attach to specific regions in virus’ DNA
- bacteria use Cas9 to cut DNA apart
CRISPR-Cas9 for gene editing
- small piece of RNA with short guide sequence binds to specific target sequence in cell’s DNA
- attached to Cas9 enzyme
- guide RNA recognises intended DNA sequence and Cas9 enzyme cuts DNA at targeted location
- DNA machinery adds or deletes pieces of genetic material to make changes to DNA by replacing existing segment with customised DNA sequence
