biotechnology and genetic modification (topic 21) Flashcards
why are bacteria useful in biotechnology and genetic modification
due to their rapid reproduction rate and their ability to make complex molecules
few ethical concerns over their manipulation
and growth
the presence of plasmids
biotechnology
The exploitation of biological processes by humans for industrial and other purposes. eg. use of bacteria in production of yogurt, yeast in production of bread
genetic engineering
Changing the genetic material of an organism by removing, changing or inserting individual genes. type of biotechnology
how are plasmids involved in genetic engineering
bacterial cells contain plasmids, which is a circle of dna, plasmids naturally pass from one bacteria to the other, in genetic modification a gene from a protein can be inserted into a plasmid, this gene will then be transferred to the genetic material of a bacterial cell, which then expresses the gene making required protein.
what is yeast
A microscopic single-celled fungus that is used in bread and beer making processes.
Yeast cells obtain their energy by anaerobic respiration
anaerobic respiration
chemical reactions in cells that break down nutrient molecules to release energy without using oxygen.
word equation of anaerobic respiration in yeast
glucose → alcohol + carbon dioxide
symbol equation for anaerboci respiration in yeast
C6 H12O6 → 2C2H5OH + 2CO2
fermentation
A metabolic process involving the conversion of carbohydrates to alcohol, often using yeast.
why is yeast used to make bread
because it releases carbon dioxide, making bread rise, ethanol released/ produced is boiled away when bread is cooked
why is yeast used to make alchol/ biofuels
beccause it releases alchol
how is yeast used to produce biofuels
the alchol produced by yeast in anerobic respiration is called ethanol, sugars from plants are the raw materials for this process or cellulose from plant cell walls (sugars are mixed with yeast and water, and kept warm in an oxygen-free atmosphere)
explain process of producing ethanol with yeast
1- biomass is harvested and delivered
2- biomass cut into shreds, pre treated, with heat and chemicals to make cellulose accesible for the enzymes
3-enzymes breaks down cellulose chains into sugars
4- yeast ferments sugar into ethanol
5- ethanol is purified through distillation
what are ways in which enzymes are used in industries
the production of fruit juice
biological washing powders.
production of lactase free milk
what enzyme is used in fruit juice production
pectinase
how and why is pectinase used in fruit juice production
Pectin is a protein that holds cell walls together. Pectinase then breaks down the pectin molecules, so that the cell walls fall apart and opening up the cells so allowing juice to be extracted more easily, also makes juice more clear.
how and why are enzymes used in biological washing powders
contain enzymes to digest (break down) the substances in fabric stains
eg protease removes blood protein- amino acids
lipase removes fats- glycerol and fatty acids
amalyse removes starch- simple sugars
why is lactose intolerance caused
lacking lactase in the body (enzymes produced in walls of intestine digests lactose to form two simpler sugars, glucose and galactose, which are quickly absorbed into the bloodstream for use in respiration)
what is used to produce lactose free milk
lactase
how is lactose free milk produced
milk is passed through a mesh that contains the immobilised enzyme of alginate beads for several cycles until no more lactose is detected
what is the difference in lactose free milk
as lactase breaks down lactose- glucose, the milk contains more sugars and thus is sweeter
what is a fermenter
designed to optimize the growth of a microorganism such as bacteria usually maid of stainless steel.
what are the structures found in a fermenter
stirrer- Keeps the microorganisms, nutrients and temperature evenly distributed
nutrients and microogransims in- such as glucose and protein, are provided for the growth of organism
Sterile air supply- Provides oxygen for the microorganism. Air is sterilised to prevent contamination of mixture by unwanted microorganism
temp and ph probes- Monitor that temperature, pH and oxygen levels remain optimal
water cooled jacket-Keeps mixture at optimum temperature
product out-Product such as insulin, mycoprotein or penicillin is removed from fermenter
what is pencicillin
an antibiotic used to control bacterial infections. It kills susceptible bacteria or prevents their growth by disrupting the production of the bacterial cell wall. This weakens the bacteria and causes them to burst when they divide. (produced in a fermenter)
how is penicillin produced
in a fermenter, solution containing sucrose is added to the tank containing Penicillium . This supplies the fungi with the nutrients they need. optimum ph and temp are kept fungi always in optimum conditions to reproduce, As the Penicillium grows, it releases penicillin into its surroundings partial harvesting takes place and carried out many times to maintain high yield
simple step by step of penicillin production
1- pencicillium added to fermenter
2- scientist seperate penciillin produced to mold
3- penicillin purified and used for antibiotics
how and why are fermenters used to make insulin
to obtain insulin for diabetic patients, using genetically engineered bacteria
what is mycoprotein
added to many food products to increase the protein content, cehap and easily made from protein
describe genetic engineering
changing the genetic material of an organism by removing, changing or inserting individual genes
how is genetic engineering used for insulin production
Human genes can be inserted into bacteria to produce human proteins such as insulin. This protein is used to treat people with type 1 diabetes
-no need to use insulin retrieved from animals, better tolerated by people with the disease
how is genetic engineering used for herbicides
insert genes into crop plants that give them a resistance to a herbicide
herbicide can be used where the herbicide-resistant plants are growing. The herbicide-resistant plants are not killed but the weeds are. This means that farmers can reduce the amount of herbicide they use, and the reduced competition with weeds increases the crop yield.
how is genetic engineering used for resistance to pests
insert genes into crop plants that give them a resistance to insect pests. eg Bt corn is maize that contains the gene for insect resistance from a soil bacterium
Bt protein does not affect mammals, fish or birds. However, there are concerns related to the use of Bt corn.
however…
-gene can be passed to other plants and they can get the resistant gene may become “super weeds”
-may harm other insects that are not pests and which are an essential part of a food chain.
how is genetic engineering used to produce food with better nutritional qualities
increasing their vitamin and amino acid contents, of crop plants
eg. food for livestock has increased amino acids reduces amount of supplements given to animal fro optimal growth
eg. golden rice for vitmamin a defficiency (vitamin a needed for good skin and eye sight, good immune system) insert genes into crop plants that make them produce large amounts of beta-carotene, produces more vitamin a
what are disadvantages of golden rice
lead to people and governments not properly recognising the need for a balanced diet
what are the main steps in genetic modification
Isolating the section of DNA that makes up the required human gene.(uses restriction enzymes)
Cutting the DNA of a bacterial plasmid.
Inserting the human DNA into the plasmid DNA. (uses restriction enzymes)
Inserting the plasmid into bacteria. (uses ligase enzymes)
Allowing the genetically modified bacteria to express the gene and make the human protein.
what enzymes are used in genetic modification
restriction enzymes and ligase enzymes
how and why are restriction enzymes used
Enzyme that cuts DNA at specific places to form sticky ends.(The ends of DNA strands after digestion. They easily re-attached to each other, so are called sticky.)
how and why are ligase enzymes used
Enzyme that joins DNA at specific places called sticky ends.make a complete length of double-stranded DNA.
recombinant plasmid
A plasmid containing a foreign gene or sequence of DNA.
disadvantages of genetically modifying crops
expensive, ethical considerations in manipulating nature, unknown long- term effects
