cloning and biotechnology Flashcards
what is vegetative propagation
natural cloning of a plant so that it is genetically identical to the parent. can take place from the stem, leaf, bud, root of the parent
what are penernnating organs and why are they important
enable plant to survive adverse conditions
contain stored food for PHS and can remain dormant in the soil. enable asexual reproduction
ie bulbs, runners, rhizomes and stem tubers
how do farmers carry out vegetative propagation
take cuttings, plant them, use rooting hormones to encourage growth of new roots
give advantages of vegetative propagation
faster, guaranteed quality of the plant
lacks genetic variation so more susceptible to environmental changes such as disease.
give advantages and disadvantages of vegetative propagation
faster, guaranteed quality of the plant
lacks genetic variation so more susceptible to environmental changes such as disease.
what is the name given to artificial cloning of plants and when is it used.
micropropagation or tissue culture
typically used when a plant does not produce seeds, is very rater, required to be pathogen free
explain how micropropagation is carried out
- a small sample of tissue is taken, meristem tissue is dissected in sterile conditions. the material removed from the plant is called the explant
- the sample is sterilised using ethanol or bleach
- the explant is put in a sterile culture medium containing a balance of hormones (auxin, cytokines) which stimulate mitosis
- the cells proliferate forming a mass of cells known as a callus. the callus is divided up into individual cell clumps and transferred into a new culture medium containing a new range of hormones for development of genetically identical platelets
- the plantlets are the potted where the grow into small plants
for and against argument of micropropagation
+ rapid production of large numbers of plants
+ disease free plants
+ increases the population of seedless plants to meet demands ie grapes and bananas
+ can grow plants that are naturally infertile ie orchids
+ increases the number of rare or endangered species
- monoculture so susceptible to environmental changes
- expensive process and requires skilled workers
- large numbers of plants can be lost during the process
- if the parent is infected with a virus then all of the clones will be too.]
give examples of cloning in animals
monozygotic twins
amphibians and reptiles can produce offspring when no male is available
star fish can regenerate themselves
flatworms can form new identical animals as part of their reproductive cycle.
how are animals artificially cloned
artificial twinning and somatic cell nuclear transfer
outline the stages of SCNT
- Nucleus is removed from the somatic cell of an adult animal
- nucleus is removed from a female gamate of the same species
- electrofusion is used to fuse the nucleus from somatic cell donor and the enucleated cell from female donor
- embryo is grown in vitro
- early embryo is split
- the embryo is then transferred into the uterus of a third animal.
the off spring is a clone of the somatic cell donor
what are problems with SCNT
can lead to premature ageing so reduces life span
what is pharming
the production of animals which have been genetically engineered. SCNT has been used in farming to produce therapeutic human proteins in milk
what is pharming
the production of therapeutic human proteins. SCNT has been used in farming to produce therapeutic human proteins in milk
outline the process of artificial twinning
- select an animal with desirable traits, treat with hormones so she super ovulated releasing more eggs which can be fertilised naturally or in the lab.
- early embryos are flushed out of the uterus. these cells are totipotent ( have the ability to form an entire new species) and are split to produce several smaller embryos each capable of growing into a full term calf.
- they are grown in a lab for a few days and then implanted into a surrogate mother to be born naturally.
outline the process of artificial twinning
- select an animal with desirable traits, treat with hormones so she super ovulated releasing more eggs which can be fertilised naturally or in the lab.
- early embryos are flushed out of the uterus. these cells are totipotent ( have the ability to form an entire new species) and are split to produce several smaller embryos each capable of growing into a full term calf.
- they are grown in a lab for a few days and then implanted into a surrogate mother to be born naturally.
what are pros and cons of animal cloning
pros
rare species
top race horses or pets
pharming and milk proteins
cons
inefficient most animals take lots of clones to have success
produces malformed offspring
likely to miscarry
shorten life span
could be taken too far
ethics
people don’t want ti eat food that has been cloned