6.4 - Cloning and Biotechnology Flashcards
define cloning
a way of producing offspring by asexual reproduction
define clone
the offspring produced as a result of asexual reproduction
define asexual reproduction
the production of genetically identical offspring from a single parent
what is vegetative propagation?
where a structure develops into a fully differentiated new plant which is genetically idential to the parent
what are examples of natural clones in plants?
- bulbs
- runners
- tubers
- rhizomes
what are the uses of natural cloning in horticulture?
- splitting up bulbs
- removing young plants from runners
- cutting up rhizomes
- cuttings
what are the advantages of cuttings?
- faster
- guarantees good characteristics
what are the disadvantages of cuttings?
- lack of genetic variation
- more susceptible to disease
what is the method for taking cuttings?
- use non-flowering stem
- make an slanted cut in stem
- add hormone rooting powder
- reduce leaves to 2 or 4
- keep cuttings well watered
- cover cutting with plastic bag for a few days
what are totipotent cells?
a cell that can differentiate into any kind of cell
e.g. zygotes
What are multipotent cells?
A cell that can form all kinds of tissues, but not whole organisms.
e.g. early embryos
What are pluripotent cells?
cells that can differentiate into a limited range of cells depending on where they are found.
Why may you use artificial cloning instead of natural cloning?
There is a limit to how many natural cones you can make from one plant.
what is micropropagation?
Making large numbers of genetically identical offspring from a single parent plant using tissue culture techniques.
When would micropropagation be used?
- selective breeding is difficult
- desired plant is rare
- Desired plant doesn’t regularly produce seeds
What is a growth medium?
Something that contains nutrients. It can even be a liquid, semi solid or solid
outline the method for micropropagation.
- dissect a small sample of meristem tissue in sterile conditions
- sterilise explant
- place explant in sterile culture medium
- cells form a callus
- divide callus into clumps and transfer to new culture medium with hormones
- plantlets potted into compost, and grow into small plants
- young plants planted out to grow
what are the advantages of micro propagation?
- produces disease free plants
- Can produce large numbers of seedless plants
- Increase numbers of rare or endangered species.
- Rapid production of a large number of plants.
Whatever disadvantages of micro propagation?
- monoculture
- expensive
- requires skilled workers
- explants are vulnerable to moulds and disease
What type of plant tissue are natural clones produced from?
Meristem.
Compare the equipment and techniques of taking cuttings with those used for micro propagation.
Taking cuttings uses less equipment.
Micropropagation produces more offspring
Outline how it is possible to produce many clones from a single, original parent plant.
micro propagation:
- explants taken from parent plant, plantlets are then subdivided
What are three advantages of vegetative propagation in agriculture?
- allows desired characteristics to be cloned
- can be done any time of year
- cheaper than micropropagation
Where is natural cloning in animals common?
in invertebrates
What’s your examples of natural cloning in animals?
- identical twins
- starfish regenerating from fragments
- hydra
- sponges
What are the two methods for artificial cloning of vertebrates?
- artificial embryo twinning
- somatic cell nuclear transfer
Outline the process of artificial embryo twinning.
- egg fertilised by IVF
- zygote divides by mitosis into ball of cells
- cells are separated and allowed to divide
- each mass of cells is placed in a surrogate uterus
What is artificial embryo twinning produce?
Offspring that are clones of each other.
What are the reasons for artificial cloning of animals?
- infertile animals can reproduce
- increase population of endangered species
- desirable genetic characteristics are always passed on
What are the reasons against artificial cloning of animals?
- time consuming
- expensive
- no gentetic variability so more susceptible to disease
- clones have a shorter life span
What does somatic cell nuclear transfer produce?
clones of the somatic cell
Outline the process of somatic cell nuclear transfer.
- somatic cell taken from donor
- unfertilised egg is enucleated
- nucleus of somatic cell placed in enucleated ovum and fused by electrofusion
- fertilised egg divides into an embryo
- embryo transferred to surrogate uterus
What are the arguments for artificial cloning in plants?
- produce seedless plants e.g. grapes
- quicker than growing plants from seed
What the arguments for artificial cloning in animals?
- allows desirable characteristics to be passed on e.g. milk producing cows
Outline the reasons against artificial cloning implants.
- aseptic technique used in micropropgation is complec and could result in mould as more susceptible to disease
Outline the reasons against artificial cloning in animals.
- reduces lifespan of animals as more susceptible to health conditions
e.g. Dolly the sheep
What is biotechnology?
Using biological organisms in enzymes for the synthesis breakdown or transformation of materials in the service of humans.
What biological organisms are used in biotechnology
- Most used enzymes in the manufacturing process or the whole organism as it is more stable.
Why are microorganisms used in biotechnology?
- no welfare issues
- can be gentically engineered
- short life cyle + rapid growth
- simple + cheap requirements
- wide range of microorganisms can carry out different processes
