Cloning And Biotechnology - Module 6 Flashcards
What is asexual reproduction a form of?
Cloning - produces genetically identical clones to parent organism and other offspring
What is the name of natural cloning?
Vegetative propagation
What are perennating organ?
Stores containing food from photosynthesis so that they can remain dormant in soil
What are the 4 structures that plant clones occur in?
- Bulbs
Leaf base swells with assimilates and develops into new shoots - Runners
Lateral stem grows away from parent plant and roots develop where it reaches ground - Rhizomes
- Stem Tubers
How are bulbs, runners and rhizomes exploited by horticulturists to produce new plants?
Bulbs are split, runners are removed from parent plant and rhizomes are cut
They increase the number of plants cheaply as well as maintaining genetic characteristics
How are cuttings made from plants? [2]
- Short sections of stem are taken and planted into the ground or pots
- Rooting hormone powder is often applied encourage new growth
How is propagation from cuttings advantageous over planting seeds?
- It is much faster
- Guarantees quality of plant as it will be an exact clone of the parent plant
What is a disadvantage of using cuttings over seed propagation?
There is a lack of genetic variation and therefore if a new disease of pest appears it may wipe out all plants
Many plant cells are totipotent.
What does this mean?
They can differentiate into all of the different cells needed in the plant
What is micropropagation?
The process of making large numbers of genetically identical offspring from a single parent using tissue culture techniques
In what circumstance is micropropagation used? [5]
- Plant doesn’t produce seeds
- Plant doesn’t respond well to natural cloning
- Plant is rare
- Plant has been genetically modified
- Required to be pathogen free
Describe the process of micropropagation
- Take a small sample of tissue from plant that you want to clone (this is the explant)
- Sample is sterilised in bleach/ethanol
- Explant is placed in a sterile culture medium containing Plant hormones for mitosis
- A mass of identical cells form called a callus
- The callus is divided up and transferred to new medium which promotes development
- Plantlets are placed into compost
What are the advances of micropropagation?
- Allowed for rapid production of crops we know will have a good yield
- Produces disease free plants
- Increases numbers of rare and endangered plants
What are the arguments against micropropagation? [4]
- Produces monoculture - many plants are genetically identical
- Expensive process requiring skilled workers
- Plantlets and explant are vulnerable to infection
- If source is infected ALL CLONES WILL BE INFECTED
In vertebrate animals, what is a form of cloning?
Monozygotic twins (identical twins)
What animals clone more commonly? Give an example.
Invertebrates
E.g starfish can regenerate a whole new animal from fragments of the original
How does cloning occur in vertebrates?
Early embryo splits to form two seperate embryos
What are the two methods use to clone mammals?
- Artificial twinning
- Somatic cell nuclear transfer
When an egg is fertilised, a ball of cells is formed.
What is a characteristic of these cells?
They are totipotent
How is artificial twinning similar to natural twinning?
In both the embryo splits - just in artificial twinning it is done manually
Who uses artificial twinning?
Used by the farming community to produce the maximum offspring from particularly good dairy or beef cattle/sheep
Describe the stages of artificial twinning?
- Cow with the desirable traits is tried with hormones so she SUPER OVULATES (releases more eggs than usual)
- The eggs are fertilised (either naturally or artificial inemination) by a bull with desired traits
- Early embryos removed from uterus
- Whilst still totipotent the cells of the early embryo are split to produce smaller embryo’s
- Split embryos are implanted into different surrogate mothers
- Lots of little cow clones born
How does artificial twinning differ in pigs to cows?
In pigs lots of embryos need to be implanted into surrogate as they are used to carrying a litter of piglets
In cows singular pregnancies are more successful
What does artificial twinning clone?
Embryos
What does somatic cell nuclear transfer clone?
Adult animals
What is an example of somatic cell nuclear transfer?
DOLLY THE SHEEP IN 1996
Describe the steps of somatic cell nuclear transfer?
- Nucleus is removed from a somatic cells of adult animal
- Nucleus is removed from a mature egg taken from a DIFFERENT FEMALE OF SAME SPECIES
- Nucleus from adult somatic cell is placed into mature enucleated egg cell
- New cell is given an electric shock to fuse and begin to divide
- Embryo will develop and is transferred into nucleus of a third animal which will be carried to term
- New animal is clone of original adult animal
Name some arguments for Animal cloning
- Artificial twinning allows high yeilding farm animals to produce more offspring than normal reproduction
- SCNT allows scientist to clone specific animals
- SCNT has the potential to enable rate, endangers and extinct animal to be reproduced
Name some arguments against animal cloning
- Cloned animals embryos often fail and either miscarry or produce deformed offspring
- Cloned animals often have shortened life spans
What is biotechnology?
The use of biological organisms to the synthesis, breakdown or transformation of materials in the service of people
What are the most commonly used organisms in biotechnology?
Fungi, Yeats and bacteria
What are microorganism ideal in biotechnology?
- No welfare issues to consider
- Range of microorganisms for different functions
- Rapid growth rate
- Nutrient requirement are often simple and cheap
What are some disadvantages of using microorganisms in indirect food production? [2]
- If conditions are not ideal they wont work
- Conditions ideal for microorganism may be ideal for making food go off
what microorganism is involved with baking?
Yeast - as it respire aerobically to make carbon dioxide letting dough rise
How is bread produced commercially?
Yeast mixture is added to ingredients, mixed and left to rise
It is then cooked in a hot oven - bred will ruse due to expansion of carbon dioxide bubbles
What happens to yeast during the baking of bread?
It is killed by the temperature
What microorganism is used in brewing?
Yeast - as it respired anarobically to produce ethanol
What are the steps in commercial brewing?
- Malting - enzymes produced by barley to break down sugars for yeast. Malt is produced.
- Mashing - malt is mixed with hot water and hops added
- Fermentation - yeast added and eventually inhibited by concentration of ethanol
- Beer is matured, filtered and distributed
What microorganism is used in cheese making?
Bacteria
Describe the process of cheese commercial making
- Milk is pasteurised (kill natural bacteria) and homogenised (fat droplets evenly distributed)
- Milk mixed with bacterial cultures and kept until separated into curds and whey
- Curds are cut and cooked in the whey and strained
- Curds are left to mature