Cloning & Biotechnology Flashcards
clones
genetically identical organisms or cells
vegetative propagation
reproduction from vegetative parts of a plant- usually an over-wintering organ
micropropagation
growing large numbers of new plants from meristem tissue taken from a sample plant
tissue culture
growing new tissues, organs or plants from certain tissues cut from a sample plant
embryo twinning
splitting an embryo to create 2 genetically identical embryos
enucleation
removal of the cell nucleus
somatic cell nuclear transfer (SCNT)
a technique that involves transferring the nucleus from a somatic cell to an egg cell
biotechnology
the use of living organisms/parts of living organisms for industrial processes- to produce food, drugs or other products
agar
a polysaccharide of galactose obtained from seaweed which is used to thicken the medium into a gel
aseptic technique
sterile techniques used in culturing and manipulating microorganisms
closed culture
a culture with no exchange of nutrients or gases with the external environment
serial dilution
a sequence of dilutions used to reduce the concentration of a solution or suspension
immobilised enzyme
an enzyme that is held in place and not free to diffuse through the solution
what process are natural clones produced by
asexual reproduction in which nucleus is divided by mitosis
why may naturally cloned cells not be physically/chemically identical
may differentiate to form 2 different types of cell after division
advantages of natural clones
conditions good, rapid, only 1 parent needed
disadvantages of natural clones
overcrowded offspring, no genetic diversity, little variation, no selection, susceptible to environ. changes
why plants are able to reproduce by cloning
many parts of the plant contain cells that retain ability to divide and differentiate into a range of types of cell
examples of vegetative propagation
runners/stolens, rhizomes, suckers, bulbs, corms, leaves, tubers
identical twins
formed when mammals clone as a zygote divides as normal by the 2 daughter cells then split to become 2 separate cells that develop individually
how to encourage cells in growing plant tissue to differentiate
apply plant growth substances to cells on a nutrient medium under sterile conditions at the correct time
advantages of artificial cloning in plants
rapid, uniform phenotype –> desirable characteristics, retain unusual combos, easier to grow/harvest, , using meristem as explant ensures virus free
disadvantages of artificial cloning in plants
labour intensive, expensive, microbial contamination -> fail, susceptible to same pests/disease
totipotent stem cells
can differentiate into any type of adult cell found in the organism in early embryo cells
arguments for artificial cloning in animals
preserve rare species, research with identical tissues allows effects of genes/hormones to be seen clearly without genotypes interfering, avoid medicinal animal testing
arguments against artificial cloning in animals
excessive genetic uniformity->unlikely to adapt to environ. changes, unknown if remain healthy long term, success rate poor, expensive, animal welfare, ethical issues with destroying embryo
metabolism
the sum total of all the chemical reactions that go in in an organism
processes in metabolism
new cells, cellular components, chemicals e.g. hormones, enzymes , waste products
primary metabolites
substances produced by an organism as part of its normal growth e.g. proteins, enzymes, lactate , production matches the growth in population of the organism
secondary metabolites
substances produced by an organism that are not part of its normal growth e.g. antibiotic chemicals , production usually begins after the main growth period
why must the air leaving the fermenter be sterilised
bacteria/microbes could be pathogenic due to mutation and spread
downstream processing
separation and purification of product from mixture in fermenter (after harvest)
advantages of using immobilised enzymes
easy, quick, continuous, renewable, protected from extreme conditions by immobilising matrix e.g. high ph/temp, reduced downstreaming costs
disadvantages of using immobilised enzymes
slower production, setting up/materials/time is expensive, less sactive than free enzymes
advantages of using microorganisms in biotechnology
production faster with demand, no ethical issues, biomass has high protein content, easily GM, not seasonal, less space needed, grow on waste
disadvantages of microorganisms in biotechnology
not eat fungal protein grown on waste, must be isolated in fermenter, needs purification, susceptible to infection, not as palatable as normal protein sources
why is asepsis important
nutrient medium also supports growth of unwanted organisms causing competition so reducing production or spoiling product with toxic chemicals -> sterile conditions must be maintained
continuous culture
primary metabolites continually released and extracted from fermenting broth (topped up with nutrients as product extracted other too densely populated)
batch culture
producing secondary metabolites where culture is set up with limited quantity of nutrients, fermenting for specific time then emptied and extracted
growth medium
broth (bottles/tubes) or agar (melted/poured in petri dishes) - contains peptones, yeast extract, salts, water and/or glucose and blood
materials microorganisms can grow on
any that provide carbon compounds for respiration and source of nitrogen for protein synthesis
liquid medium
a liquid broth that is initially clear but turns cloudy when bacteria grows, useful to increase numbers before transferring to agar
why serial dilutions are used to investigate rate of growth of the population of microorganisms
population density must be reduced otherwise there’d be too many colonies merging together, impossible to count
how methods are used to immobilise enzymes
by binding them to a surface/simply trapping them so can’t enter substrate solution
advantages of non-reproductive cloning
genetically identical so won’t be rejected by immune system, reduce problems of waiting for donor organs, totipotent so used to generate any cell type and repair damage otherwise can’t be repaired, less dangerous
aseptic techniques
developed to reduce likelihood of contaminating medium with unwanted bacteria/fungi
single-celled fungi grow as…
circular colonies- a mass of hyphae
factors that affect growth of microorganisms in a fermenter
temperature, nutrients, oxygen, pH, concentration of product
bioremediation
use of microorganisms to clean the soil and underground water on polluted sites
advantages of bioremediation
uses natural systems, less labour/equipment, treatment in situ, few waste products, less risk of exposure to clean-up personnel
disadvantages of bioremediation
only suitable for certain substances so can’t treat heavy metals
