Biotechnology 2 Flashcards
Clone
Genetically identical to the original organism cloned dna which was copied from donor
Naturally occurring clones
Identical twins
Asexual reproduction : in plants via mitosis; in bacteria via binary fission
Vegetative propagation techniques
Involves peen sting organs which helps survive adverse conditions
Eg Root suckers, tubers , bulbs and runners
Rhizomes/ root suckers
A specialised horizontal running stem underground often swollen containing food
Develop buds along stem forming new vertical shoots forming independent plants
Tubers
Eg potato
Tip of underground stem becomes swollen with stored food forms a tuner or storage organ these can develop new shoots (eyes on a potato)
Bulbs
The leaf bases swell with stored food from photosynthesis buds form internally which develop into new shoots in the next season
Eg onion
Runners
Eg spider plant
Shoots grow out from parent plant where they touch the ground
roots and leaves start to grow forming new plant
Artificial vegetative propagation techniques
Faster than growing seeds
Cuttings and Grafts
Cuttings
Cut between nodes cut end into the soil and roots develop over time
Can use auxin to encourage root development
Grafts
Shoot section removed from tree
An already growing stem has a wedge cut into it
Stem removed is inserted into hole
Graft is then genetically identical to the cutting plant but the rootstock is not
Micropropagation
Obtain sample ( break up plant into ex plants)
Sterilise tissue ( lab + solution)
Culture explanation nutrient agar
Callus divided ( undifferentiated mass)
Put callus in nutrient rich soil and allow to grow
Evaluating microprop.
Advantages- produce 100s from 1 plant
Guaranteed outcome
Useful for high value plants eg extinct risk
Rapid production of plants with genetic make up that produce high yield
Disadvantages- expensive technique must be kept sterile in labs
Monoculture produced susceptible to disease
Biotechnology
Exploitation of organisms of their processes to make a product or process
Forms of organism exploitation
Food and drink production
Drugs and medicine
Commercial chemicals
Bioremediation of waste products
Food and drink biotech
Prevent food spoilage - ferment
Improved taste - beer wine and cheese
Direct food production - fungi and quorn
Evaluation of using biotech in food
Advantages - rapid production ; high protein little fat ; can use waste to grow (low cost) easily genetically modified; no welfare issues
Disadvantages- can produce toxins if climate incorrect; need sterile conditions; concern over GM foods ;protein has to be purified
Drugs and medicine biotech
Production of drugs eg penicillin antibiotic produced by Penicillium notatum/ chrysogenum - needs high O2 and sensitive to temp ( stage 1- fungus growth/stage 2- penicillin production)
Genetically engineered bacteria produce human bacteria for patients w diabetes
Bioremediation biotech
Natural microbes break down organic matter into co2 and water - microbes break down and neutralise contaminants
GM organisms develop bacteria to remove mercury from water v harmful
Immobilising enzymes
Isolated enzymes used in industry so can catalyse the reaction but not freely with the substrate
Evaluation of immobilised enzymes
Advantages- enzymes are not present with products so downstream process is low ; immediately available for reuse; more stable at high ph and temp matrix protects
Disadvantage- expensive set up ; less active do not freely mix; contamination costly stop system
Methods of immobilising enzymes
Entrapment
Covalent bonding
Membrane separation
Adsorption
Entrapment
Enzyme trapped in gel bead
Reduced rate as substrate need to get through trapping barrier
Less available active site
Adsorption
Enzyme mixed w immobilising support bond using hydrophobic interactions and ionic links
Forces aren’t strong enzymes can be detached
Active site displayed high rate
Covalent bonding
Enzyme are covalent bonded to a support to insoluble material using cross link agent
Binding is v strong and little leakage high rate but doesn’t immobilise large quantities
Membrane separation
Enzymes physically separate using partially permeable membrane
Substrate small enough to pass through membrane and product pass back out
Animal cloning techniques
Splitting embryos/ artificial twinning
Somatic cell nuclear transfer
Artificial twinning
Create identical twins
In vitro fertilisation artificial split fertilised egg up to 6 days (egg is totipotent)
Implanted into surrogate mother
Somatic cell nuclear transfer
Nucleus is removed from egg
Diploid nucleus from donor placed into egg
Egg is stimulated to divide and forms embryo (here can be split)
Implanted into surrogate mothers
Why use surrogate mothers
Make results far more obvious that offspring were from cloning rather than fertilisation- distinct genetic difference
Evaluation of animal cloning
Advantages- high yield animals many more offspring compared to normal reproduction; enables male to pass on desirable genes easier; scnt helpful in pharming ; clone race horses/ save endangered species
Disadvantages- inefficient ; miscarry/produce malformed offspring; shortened life span; unsuccessful bringing back extinct species
Culturing microorganisms
Growing large enough to see cultures w naked eye for medical diagnosis/ scientific experiments
Conditions for culturing
Correct conditions of temp O2 and pH
Nutrient medium - liquid form (broth) or solid form (agar) - allows to multiply rapidly
Must be kept sterile via asepsis
Aseptic techniques
Getting rid of unwanted microorganisms
-Uv light
-Laminar flow cabinet
-Disinfecting work areas
-Filters on inlets and outlets
-Sterilise equip using blue flame
Inoculating broth
Bacteria added to known amount of nutrients
Stopper in flask to prevent air contam
Incubate at suitable temp shaking reg to provide O2
Inoculating agar
Wire inoculating loop sterilised via flame (cool)
Dip into bacteria suspension add to agar in zigzag streak
Lid onto dish hold down w tape not sealed so prevent growth of anaerobic bacteria
Growth stages of bacterial colonies
Bacteria asex reprod every 20mins
Log used to rep as difference is too great
1. Lag phase - bacteria adapt to new environ
2. Exponential phase- reprod is close to its theoretical max
3. Stationary phase- growth rate is zero death/new cells same
4. Death stage when reprod has ceased
Limiting factors in growth of bacteria
Nutrients available run out as more bacteria
Oxygen levels pop rises more demand
Temp - if temp too high enzymes denature
Toxic waste build up
Change in pH as CO2 incr pH of culture falls affecting enzyme activity thus pop growth
Primary metabolites
Formed during the growth stage as a result of energy metabolism
Eg alcohols amino acids and enzymes
Secondary metabolites
Substances produced by an organism which are not essential for normal growth - organism would not suffer in the short term without them
Eg toxic chemicals or penicillin
Formed near end of growth phase/stationary phase
Bacterial population techniques
Count directly using microscope however have to use specialised slide and can’t differentiate between dead or alive bacteria
Dilution playing making serial dilutions and counting no of colonies - may be a poor representation of original sample however
Bioprocesses
Ways of growing microorganisms
Batch fermentation
Continuous culture
Batch fermentation
microorganism added to a fixed volume of medium
Nutrients start to use up and waste builds up
As culture reaches stationary phase begin to carry out biochemical changes (2nd metabolites) - desired products
Stopped before death stage and products harvested and sterilised system
Continuous culture
Microorganisms added to sterile nutrient medium
Nutrient medium continuously added once reached the exponential point of growth
Culture broth removed keeping culture volume constant
To produce primary metabolites
More products lost if contamination occurs
