6.2 Cloning and Biotechnology Flashcards
What is cloning?
the process of producing genetically identical cells or organisms from existing cells or organisms
Natural Cloning
what is vegetative propagation?
the production of plant clones from non-reproductive tissues e.g roots, leaves and stems
what are rhizomes?
- stem structures that grow horizontally underground away from the parent plant.
- they have nodes from which new shoots and roots can develop
what are runners?
- stem structures that grow above ground on the surface of the soil.
- new shoots and roots can either develop from nodes or form at the end of the runners
what are suckers?
- shoots that grow from sucker buds (undeveloped shoots) present on the shallow roots of a parent plant.
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what are tubers?
- large underground plant structures that act as a food store for the plant
- they’re covered in ‘eyes’.
- each eye is able to sprout and form a new plant
what are bulbs?
- underground food stores used by plants, such as onion plants.
- new bulbs are able to develop from the original bulb and form new individual plants
How do you produce a clone from cuttings?
1) Use a scalpel to take a cutting from the end of a stem of your parent plant.
2) Remove the leaves from the lower end of the cutting, leaving just one at the tip.
3) Dip the cut end of the stem in rooting powder, which contains hormones to induce root formation.
4) Then, place the cutting in a suitable growth medium, such as well-drained compost.
5) Provide the cutting with a warm and moist environment.
6) When the cutting has formed its own roots and is strong enough, you can plant it elsewhere to continue growing.
What are the methods of natural cloning?
- Vegetative propagation
- Cuttings
what is micropropagation?
the process of taking a small piece of plant tissue and using plant growth substances to encourage it to grow and develop into a whole new plant
How are artificial plant clones produced?
using tissue culture
Describe the process of tissue culturing
1) Cells are taken from the original plant that’s going to be cloned.
2) Cells from the stem and root tip are used because theyre stem cells.
3) The Cells are sterilised to kill any microorganisms.
4) The Cells are placed in a culture medium containing plant nutrients and growth hormones.
5)When the Cells have divided and grown into a small plant, they’re taken out of the medium and planted in soil
What are the positives of artifical cloning?
- Desirable genetic characteristics are always passed on to clones. This doesn’t always happen when plants reproduce sexually.
- Tissue culture allows plants to reproduce in any season because the environment is controlled.
- Less space is required by tissue culture .
- Lots of plants are produced very quickly compared with growing plants from seeds.
- Using the apical bud(merristems) as an explanation ensures that the new plants are free from viruses
What are the disadvantages of artifical cloning?
- Undesirable genetic characteristics are always passed on to clones.
- Cloned plant populations have no genetic variation, so a single disease could kill them all.
- Production costs of tissue culture are very high due to high energy use and the training of skilled workers.
- Contamination by microorganisms during tissue culture can be disastrous and result in a complete loss of the plants being cultured.
What is an example of natural clones in animals?
Twins
What are the methods of artifical cloning in animals?
Artifical embryo twinning AND Somatic cell nuclear transfer
Describe the process of Artificial embryo twinning
1) An egg cell is extracted from a female cow and fertilised in a petri dish.
2) The zygote(the fertilised ehg) is left to divide by mitosis to form an embryo .
3) Next, the individual cells from the embryo are separated and each put into a separate petri dish. Each cell divides and develops normally, so an embryo forms in each petri dish
4) The embryos are then implanted into female cows which act as surrogate mothers.
5) The embryos continue to develop inside the surrogate cows and eventually offspring are born.
All the offspring will be genetically identical to one another
Describe the process of somatic cell nuclear transfer
1) A somatic cell (any cell that isnt reproductive) is taken from Sheep A to be cloned and its nucleus is removed.
2) An immature egg cell is taken from sheep B and the nucleus is removed, enucleation.
3) The nucleus from sheep a is inserted into the enucleated egg cell. The egg cell from sheep B now contains the genetic information from sheep A.
4) The nucleus and the enucleated egg cell are fused together and are stimulated to divide by an electric shock.
5) The shock also triggers the egg cell to start developing as though it has just been fertilised. This produces an embryo
6) The embryo is then implanted into the uterus of a surrogate mother. Eventually a lamb is produced that is a clone of Sheep A.
What are the uses of animal cloning ?
- Research purposes.
- Saving endangered animals from extinction
- Farmers increasing the number of animals with desired characteristics
- GM animals could produce useful substances that they wouldn’t normally produce
- Embryonic stem cells can be cloned and these could be used to replace damaged tissues
What are the advantages of animal cloning?
- Desirable genetic characteristics are always passed on to clones, which doesn’t always happen with sexual reproduction.
- Infertile animals can be reproduced.
- Increasing the population of endangered species helps to preserve biodiversity.
- Animals can be cloned at any time, you don’t have to wait till breeding season
- Cloning can help us develop new treatments for disease, which could mean less suffering for certain people.
What are disadvantages of animal cloning?
- Animal cloning is very difficult, time consuming and expensive.
- There’s no genetic variation in cloned populations so undesirable genetic characteristics are always passed on. This means that all the cloned animals in a population are susceptible to the same diseases.
- Some evidence suggests that clones may not live as long as natural offspring.
- Using cloned human embryos as a source of stem cells is controversial. Some people see it as the loss of a human life
What is biotechnology?
Biotechnology is the industrial use of living organisms to produce foods, drugs and other products
Why are microorganisms used for biotechnology?
- Their ideal growth conditions can be easily created, they’ll generally grow successfully if they have the right nutrients, temperature, pH, moisture levels, and availability of gases.
- Because of their short life cycle, they grow rapidly and so products can be made quickly.
- They can be grown on a range of inexpensive materials, this makes their use economically viable
- They can be grown at any time of the year.
What are intracellular enzymes?
Enzymes contained within cells