Cloning and Biotechnology Flashcards
Clones Definition
GENETICALLY identical copies
what is vegetative propagation
production of plant clones from non reproductive cells
what are rhizomes
stem structures that grow horizontally UNDERGROUND away from the parent plant e.g bamboo
what are runners
stem structures that grow horizontally ABOVE GROUND e.g strawberries
what are tubers
large underground plant structures that act as a food store for the plant e.g potatoes
what are bulbs
underground food stores where bulbs can develop from the og plant to form new individual plants e.g onions
How to take plant cuttings as an example of a simple cloning technique
From Stem: using a scalpel take a cutting 5-10cm from end of a stem of a parent plant, remove leaves at lower end of the cutting leaving one at the tip, dip the lower end into rooting powder with growth hormones, place this cutting in a pot with suitable growth medium, provide warmth using a propagator
what is tissue culture
growing new tissues/organs/plants from certain tissues cut from parent plants
what is micropropagation
growing large numbers of plants from meristem tissues from parent plant (mass tissue culture baso)
process of tissue culture/ micropropagation
cut a developing stem/ root (explant) as they have stem cells. sterilise this explant to kill any microorganisms. place CELLS in a culture containing growth hormones , glucose amino acids. cells will divide to form a small plant, move to soil. plants are identical to parents
when is micropropagation used
- Desirable plant doesn’t produce many seeds
- rare plants
- GM plants
- doesn’t respond well to natural cloning
Advantages of micropropagation
- infertile plants can be grown
- plants can be grown in any season
- desirable characteristics always passed on
- quicker growth than seeds
Disadvantages of micropropagation
- unfavourable characteristics always passed on
- susceptible to disease due to lack of genetic variation
- high production cost- skilled workers + energy
- contamination can be disastrous
natural clones in invertebrates:
starfish regenerating fragments
natural clones in vertebrates
MZ twins
Process of artificial embryo twinning
egg is extracted from female animal and fertilised in a Petri dish- fertilised egg left to divide Into an embryo, cells from this are then put into a separate Petri dish and left to divide into an embryo, these embryos are implanted into more female animals which act as surrogates, embryos develop and OFFSPRING ARE GENETICALLY IDENTICAL TO EACH-OTHER.
process of somatic cell nuclear transfer
Somatic cell extracted from target animal, the nucleus is extracted and kept. from another animal an egg cell is taken and enucleated (nucleus removed). the nucleus from animal 1 is inserted into animal 2s egg cell and fused and stimulated to divide using electrofusion. this forms an embryo- implanted into surrogate mother, offspring is identical to animal 1
arguments for artificial cloning in animals
- desirable characteristics always passed on
- infertile animals can reproduce
- breeding season doesn’t matter
- save endangered species
arguments against artificial cloning in animals
- ethics, embryos destroyed in process
- undesirable characteristics always passed on
- no genetic variation
- difficult to do and time consuming
- cloned offspring don’t live as long as natural ones