chapter 22 - biotech and cloning Flashcards
What is vegetative propagation?
- asexual reproduction by plants
- new plants grow from parts of parent plants and are genetically identical
What are some examples of vegetative propagation?
- the onion of bulbs
- the potato of tubers
- the ginger of rhizomes
- the strawberry of runners
- the elm of suckers
What are the two types of artificial plant cloning ?
- cuttings
- tissue culture
What is the process of cuttings when artificially cloning a plant?
- remove the shoot tip
- clean cut through the xylem and phloem
- apply rooting powder to cut end (contains auxin)
- transfer to soil
- control conditions (propagator or greenhouse)
- roots + shoots develop
What is the process of enucleation and somatic cell transfer?
- enucleate(remove the nucleus) an egg cell
- remove a nucleus from a somatic cell (diploid body cell)
- inject somatic nucleus into enucleated egg cell
- then an electro shock is carried out
- embryo grown in vitro(test tube) until embryo splits (blastocyst)
- embryo inserted into the womb of a surrogate mother
- embryo is genetically identical to parent who donated the somatic nucleus
What is the process of tissue culture when artificially cloning a plant?
- take small pieces from parent plant(shoot tip)
- Sterilize explant to kill microorganisms (bleach)
- use aseptic technique
- put on a growth medium(agar plate), containing glucose and amino acids and nitrates
- add growth hormones (auxin and cytokinin)
- this forms the callus (unspecialised cells)
- subdivide callus to make many cells
- change plant hormone ratio, the roots and shoots start to form
- transfer to soil (propagator)
What are the three types of animal cloning?
- enucleation and somatic cell nuclear transfer
- artificial embryo twinning
- natural cloning
What is the process of artificial embryo twinning?
- egg is fertilised in vitro(zygote formed)
- zygote divides to form an embryo
- unspecialised early embryo cells are separated
- each cell develops into a new embryo
- embryo grown in vitro
- until embryo splits
- embryo inserted into womb of a surrogate mother
- embryo genetically identical to each other (not either parent)
What is the process of natural cloning?
- occurs naturally
- fertilised egg forms the embryo
- embryo splits into two or more cells
- identical twin are produced
What are the uses of animal cloning?
- used in farming, make exact copies of high yielding phenotypes(high milk yield)
- transformed organisms can be used to make useful products
- source of embryonic stem cells
- conservation of highly endangered species
- drug research
What are the advantages and disadvantages of both animal and plant cloning?
advantages:
- all offspring will be genetically identical
- will have the desired trait
- faster than artificial selection
- infertile organisms can be reproduced
disadvantages:
- no genetic diversity in offspring so are more susceptible to disease
- cloning success rate is low
- expensive + labour intensive
What are the advantages and disadvantages of just animal cloning?
advantages:
- all offspring will be the same sex
- avoids mating risks
disadvantages:
- cloned animals have a shorter lifespan
What are the advantages and disadvantages of just plant cloning?
advantages:
- faster than growing from seeds
- plants can be cultured indoors
- can be produced at any season
disadvantages:
- contamination can destroy whole crop
What is biotechnology?
- commercial use of living organisms / enzymes to make useful products
What are the advantages of biotechnology?
- fast growth + reproduction
- easy + cheap to culture
- done at low temps and low pressures
- microorganisms can be genetically engineered
- products easy to purify + separate
What are the disadvantages of biotechnology?
- can be contaminated easily as there are ideal conditions for microorganisms
- less publicly accepted as the the food is grown on waste
What are the three uses of biotech?
- food
- drugs
- industry
how is biotech used in drugs?
- penicillion made from fungus penicillion
- insulin made from transformed bacteria
how is biotech used in food?
- cheese made from fungi in blue cheese
- yoghurt is made from lactobacillius
- beer and bread is made from yeast
- mycoprotein is made from fungus
how is biotech used in industry?
- enzymes, lipases in detergents
- biogas, yeast
what are the two ways in which results are produced from working with biotech and microorganisms?
- batch culture
- continous culture
What are the 4 stages of batch culture?
- lag phase
- log phase (exponential)
- stationary phase
- death phase
Explain what is happening in the 4 stages of batch culture
Lag phase:
- genes activated(lactose permease)
- this means that enzymes are transcribed and translated
- substrate starts being broken down
- slow population growth
Log phase:
- rapid population growth
- abundant nutrients
- cell production > than cell death
stationary phase:
- cell production = cell death
- lack of nurtrients/build up of waste products
- carrying capacity reached
Death phase:
- cell death > than cell production
- lack of nutrients/ build of waste
- expression of antimicrobial compounds
What is the method for batch culture ?
- closed fermentation vessel used:
- this means that microorganism + nutrients added at the start and nothing added or removed
- products seperated at the end
- temp is usually controlled (e.g water jacket)
- puddles/aeroters used to stir, this evens the distrubution of nutrients
- nutrients depleted at the end
what is the method for continous culture?
- open fermentation vessel
- nutrients added and products removed at a constant rate
- maintains microorganisms in exponential phase
- conditions kept constant (e.g. temperature, ph, glucose, o2)
What are immobilised enzymes?
- enzymes that are attached to inert materials, this makes them more stable (ph + temp) and easier to remove from the product
what are the types of immobilised enzymes?
- bind enzymes onto a matrix(e.g cellulose)
- ionic bond onto a solid support (e.g resin/glass)
- covalently bond onto substrate(cellulose/another enzyme)
- Enlcose on a partially permeable membrane(microcapsules)
- immobilise inside beads(alginate)
What are the advantages of using immobilised enzymes over free enzymes?
- enzymes can be reused, the less that are used the more money saved
- purification costs reduced
- more stable so function at higher temps and wider range of ph
- many enzymes can be used together
