6.4 Cloning and Biotechnology Flashcards
What is natural cloning ?
Where new plants are propagated from stem, leaf or root to become independent from its parent. Root hormone is added to encourage growth of new roots.
Positives and negatives of natural cloning ?
Much faster, guarantees quality of plants, however there is lack of genetic variation so may be harmed by disease or pests.
What is micropropagation ?
Process of making large numbers of genetically identical offspring from a single parent plant using tissue culture techniques. Used when desired plant does not readily produce seeds, rare, GM with difficulty and are required to pathogen free.
What is the process of micropropagation ?
Small sample is taken from plant.
Sample is sterilised by placing in a culture medium containing plant hormones.
Callus forms and is divided up and transferred to a new culture medium.
Platelets are potted and wound plants grow.
Benefits to micropropagation ?
Allows for rapid production of crops
Produces disease free plants and seedless plants.
Grow infertile plants and can produce more endangered plants.
Negatives of micropropagation ?
Producing monoculture
Expensive process
Vulnerable to infection
All clones are affected by disease so large numbers of plants can be lost.
How is artificial cloning done in animals ?
Cow is treated with hormones to over ovulate.
Ova produced is inseminated and mature eggs are removed and fertilised. Early embryo is split to produce many.
Grown in lab and implanted into surrogate mother.
Embryos develop and are born normally.
What is somatic nuclear cell transfer ?
Nucleus from adult somatic cell is transferred to an enucleated egg cell. Uses tiny electric shocks to fuse egg and nucleus. First done with Dolly the sheep.
What are positives and negatives with somatic nuclear cell transfer ?
Produce more offspring than normal and desirable genes are passed on. However it is an inefficient process, embryos fail to develop and have a shortened lifespan. Is very unsuccessful so far.
What is biotechnology ?
Applying biological organisms to synthesis, breakdown or transfer of materials.
No welfare issues, short life cycle and simple and relatively cheap.
What is bioremediation ?
Use of biological systems to remove soil and water pollution.
How is Baking done ?
Yeast respires aerobically. Mixed, kneaded and CO2 expands.
How is Brewing done ?
Yeast respires anaerobically. Malting, mashing, fermentation and maturation.
How is cheese-making done ?
Bacteria feeds on lactose. Milk is pasteurised and mixed with bacterial cultures.
How is yoghurt making done ?
Bacteria produces extracellular polymers. Milk powder is added and pasteurised.
What is Quorn ?
Single-cell protein made from a fungus grown in large fermenters using glucose syrup. Microorganisms are combined with albumen and compressed to form meat substitutes.
Advantages of micropropogation ?
Microorganism reproduce fast
High protein content
Variety of waste materials used.
Can be GM to produce protein
Not dependent on weather
No welfare issues.
Disadvantaged of micropropagation ?
Produces toxins if condition are not maintained.
Have to be separated from nutrient
Needs sterile conditions that are controlled.
Involves GM organisms which may have concerns about eating.
Protein has to be purifies and there is little flavour.
How is penicillin produced ?
Need high oxygen levels and rich nutrient medium to grown well. Sensitive to pH and temperature. Process uses small fermenters in order to maintain high levels of oxygen. Mixture is continually stirred in the rich nutrient medium. Contains buffer to maintain pH at 6.5 and remained temperature of 25 degrees.
Natural organisms in bioremediation ?
Many microorganisms naturally break down organic material to produce CO2 and H20. They break down and neutralise many contaminants.
GM organisms in bioremediation ?
To develop GM bacteria which can break down or accumulate contaminants which they would not naturally encounter. Eg bacteria can remove mercury from water.
What is an inoculating broth ?
Make suspension fro bacteria to grown and mix volume with sterile nutrient medium. Stopper flask to prevent contamination with air. Incubate and shake regularly.
What is inoculating agar ?
Wire loop is sterilised by bunsen flame. Dip loop in bacterial suspension. Use zigzags across agar to apply bacteria in streaks. Replace lid and incubate.
What is lag phase?
When bacteria are adapting to their new environment. Growing and synthesising enzymes.
What is log/ exponential phase ?
Rate of bacterials reproduction is close to theoretical maximum.
What is the stationary phase ?
Total growth its 0.
What is the death phase ?
Reproduction has almost ceased and death rate of cells increases.
What are some limiting factors of bacterial growth ?
Nutrients available, O2 levels, temperature, build up of waste, change in pH.
What are primary metabolites ?
Substances produced continually throughout.
What are secondary metabolites ?
Substances produced during certain circumstances.
What is batch fermentation ?
Process is topped before the death phase and products are harvested. Whole system is cleaned up and a new batch culture starts.
What is continuous fermentation ?
Nutrient media is added continually once exponential growth is reached. Culture broth is continually removed.
Advantages of immoblised enzymes ?
Less wasteful, more efficient by working at higher concentrations, no unwanted enzymes present, isolated enzymes can be given ideal conditions for maximum production.
Are free enzymes wasteful ?
Yes as usually cannot be recovered at end of the process.
How do immobilised enzymes work ?
Attached to inert substrate which passes over turning into a product. They are held in place so can be recovered from reaction mixture and reused over time. They do not contaminate end product, so less downstream processing is needed.
What is surface immobilisation (adsorption)?
Adsorption to inorganic carriers.
+Simple and cheap
+ Enzymes are accessible
- Enzyme can be lost from matrix.
What is surface immobilisation (covalent/ ionic bonds)?
Covalent or ionic bonds to inorganic carriers.
+/- cost varies
+Enzymes strongly bound and accessible
+pH and substrate concentration have little effect.
-Active site can be modified.
What is entrapment ?
Enzymes are attached in matrix.
+Widely adapted to different processes
-Can be expensive
-Difficult to entrap and diffuse.
-Effect of entrapment varies depending on matrix.
