Module 6.2.1 - Cloning and Biotechnology Flashcards
What are natural clones?
Genetically identical copies
e.g. mitosis, asexual reproduction (budding yeast, binary fission)
What are some advantages of natural cloning?
- dont need a mate
- pass on advantageous alleles
- quicker pop increase
- condition good for parents are good for offspring
What are some disadvantages of natural cloning?
- lack of genetic variation
- conditions may change and be unsuitable
- offspring may become overcrowded
- selection not possible
- whole pop susceptible to changes in environment
- little variation/diversity
What is vegetative propagation?
Plants that can reproduce asexually by cloning as they have many cells that retain ability to differentiate
e.g. spider plants, suckers, bulbs, leaves
What is a clone?
Genetic copy of another organism
What is tissue culture?
Growing new tissues, organs or plants from certain tissues cut from sample plants
What is micropropagation?
Growing large numbers of plants from meristem tissue taken from a sample plant
When is micropropagation used?
Desirable plant:
- doesn’t produce many seeds
- doesn’t respond well to natural cloning
- is rare
- is GM or selectively bred
- needs to be pathogen free
What is the process of micropropagation?
- cells taken from shoot
- cells sterilised before being placed onto nutrient medium
- explants placed on sterile growth medium, forms callus culture, divided to produces lots of small clumps of undifferentiated cells - transferred to new agar medium, plantlets grow
- plantlets are transferred into compost
What are some advantages of micropropagation?
- quick
- disease free plants
- increase pop of rare plants
- larger number of seedless plants
- naturally infertile plants can be grown
What are some advantages of micropropagation?
- monoculture
- expensive, skilled workers needed
- explants and plantlets vulnerable to mould during process
- if source infected with virus, new plants will be infected
How do invertebrates clone?
Regenerate an entire organism from just a fragment of original
Hydra - small buds on side of bodies that eventually live independently, small aquatic animals
What is the process of artificial embryo twinning?
- fertilised egg created using IVF
- Zygote divides by mitosis to form ball of cells
- Cells are separated and allowed to continue dividing
- Each mass of cells is placed into uterus of surrogate mother
What are the arguments for artificial cloning in animals?
- increase pop of rare species
- pass on advantageous characteristics
- supply stem cells
- develop new disease treatments
- control in testing on animal clones
- infertile pop of endangered
What are the arguments against artificial cloning in animals?
- expensive
- time consuming
- doesn’t continuously work
- death of foetus and animal welfare problems when it fails
- no genetic variability
- may not live as long as natural offspring
What is SCNT?
Somatic cell nuclear transfer
How does SCNT work?
- Nucleus is removed (enucleated) from an egg cell and fused with the nucleus from a somatic cell
- An electric shock fuses to form zygote
- An embryo of clones is formed by mitosis
- Embryo placed into surrogate and the clone is birthed
How is penicillin produced?
Batch culture, Penicillium Chrysogenum, secondary metabolite
- fermenter ran for 6 days and filtered
- potassium compounds added and precipitated as crystals
- antibiotic prepared for administration of tablets, syrups, injections
How is insulin produced?
Treat diseases, GM Escherichia Coli
- continuous process
- GM bacteria
- inserted into bacterium using plasmid
- produce vast quantities
How is bioremediation produced?
Pseudomonas Putida
- microorganisms clean spoil and underground water on polluted sites,
- convert toxic substances to less harmful ones
- stimulate growth of microbe
- uses contaminant as source of food
How is a single cell protein produced?
Mycoprotein, Fusarium Venenatum
- microorganisms produce proteins for human food
- grown any organic substrate
How is yeast used in brewing?
Anaerobically, S. Cerevisiae
- fermentation, malting, mashing, fermentation, maturation, finishing
Glucose -> ethanol + CO2
How is yeast used in baking?
Aerobically, S. Cerevisiae
Glucose + CO2 -> CO2 +H2O, CO2 makes bread rise
- yeast cells killed during cooking
- bubble from CO2 expand from high temp
What is the cheese making biotechnological process?
Bacteria fed on lactose to produce lactic acid
lactose -> lactic acid
- milk pasteurisation, homogenised, bacteria and chymosin added, separated, cottage cheese, harder cheese
Lactococcal and Lactobacilli
What is the yoghurt production biotechnological process?
S. Thermophilus and L. Bulgaricus, anaerobically
lactose -> lactic acid
- bacteria fed on lactose to produce lactic acid
- sterilise, pasteurisation of milk, add bacteria culture, incubate, sampling, add flavours/colours, quality control
What are the advantages of using microorganisms?
- no welfare/ethical issues
- health benefits
- less waste
- can speed up processes
- controlled conditions
- not affected by seasons
- not much land needed
What are the disadvantages of using microorganisms?
- GM bacteria expensive
- specific conditions
- may cause contamination
- not wanting fungal protein
- protein has to be purified
What are the 4 stages on an exponential growth graph and what happens at each stage?
- Lag phase - time to synthesise enzymes
- Exponential/log phase - nutrients/enzymes in plentiful supply
- Stable/stationary phase - resources become limiting factors, build up of waste products
- Death phase - one or more resources used up, waste products built up to toxic levels
What is batch fermentation?
- continuous closed system
- only wastes 1 batch if contaminated
- easier and less monitoring needed
- microorganisms inoculated into fixed volume medium
- waste builds up
- stationary phase
- secondary metabolite
- cleaned and started again
What is continuous fermentation?
- continuous addition of nutrients and emptying of products
- prevents death phase
- contamination more likely
- more monitoring needed
- primary metabolite
- waste, products, cells removed regularly to keep conditions optimum
What is primary metabolite?
Produced all the time
What is secondary metabolite?
Produced at certain times
What are immobilised enzymes?
Enzymes that can’t move as they are attached to a substrate which keep it in place
What are some advantages of immobilised enzymes?
- saves money
- can reuse enzymes
- no contamination
- active over a wider range of temps and pH levels
- less effected by fluctuations
What do immobilised enzymes turn lactose into?
Glucose and galactose
What are the 3 main methods of immobilised enzymes?
- adsorption
- covalent bonding
- entrapment
What is the adsorption method?
Enzymes bound to supporting surface
- hydrophobic interactions and ionic links
- enzymes stay exposed to substrates
- can distort active site and reduce activity
- bonding forces not always strong so can become detached and leak into reaction mixture
What is the covalent bonding method?
Enzymes bonded into supporting surface using covalent bonds
- not likely to become detached
- expensive
- can distort active site and reduce activity
What is the entrapment method?
Enzymes trapped within a gel/matrix
- doesn’t allow free movement
- not bonded so won’t distort active site
- remains fully active
- substrate must diffuse into environment matrix
- product must diffuse out
