selective breeding booklet Flashcards
what is selective breeding
process by which humans breed plants/animals for specific characteristics
what does selective breeding ensure
genes for a specific characteristic remain in the population
give 4 reasons why selective breeding may be done:
- make diesease resistant crops
- animals that profucemore meat or milk
- grow large/unusual flowers
- breed gentle dogs
explain they process of selective breeding:
- benifical characteristic selected from one organism
- breed w an organism also possessing a beneficial characteristic
- select off spring
- repeat for many generations = smaller gene pool
how can you selectively breed plants
- desired characteristic in plant identified the pollen [male gamete]
- placed kn the stigma of another plant w desired characteristics
- collect seeds / offspring plants
- repeat
what are the 3 main problems with selective breeding?
- reduction in gene pol
- inbreeding can result in health problems
- new diseases and defect can occur
why is a reduction in gene pool bad
- number of different alleles in population decrease
- alleles w non desired characteristics can be lost
- all off spring = inbred
how can inbreeding result in healthy problems
inbreeding = alleles all very similar
- if one allele has a harmful genetic defect it is likely for it to be passed to offspring
- reduces gene pool = less variation
how can new diseases form w selective breeding
reduces genetic variation
what does genetic engineering involve
MODYFYING THE GEONOME of an organism by introducing a gene from another organism to give a desired CHARACTERISTIC
give 2 times generic engineering is used:
- make plants resistant to disease / produce bigger plants
- bacteria cells GM to produce human insulin
what does transgenic mean
when organism have been given genes form other organisms
what is the method for genetic engineering
- DNA is removed from the cell nucleus
- RESTRICTED ENZYMES isolate required gene and cut the either sided of target gene
- simultaneously scientists remove a plasmid DNA from a bacterium
- scientists cut open the plasmid with the same restricted enzyme
- the human DNA wil then attatch to plasmid DNA making new loop
=RECOMBINANT DNA
name 4 examples of genetic engineering:
- TREATING DIABETES
- GENETICALLY MODIFIED CROPS
- GENERICALLY MODIFIED SHEEP
- GENE THERAPY
how can GM test diabetes
bacteria have been GM to produce human insulin for diabetics
how is GM usefull for crops
increase yield, increase size, quality, disease/herbicide RESISTANT
why is GM sheep good
produce specific substances in their milk
why is GM good for gene therapy
GM treatments for people with inherited diseases
what are the 4 pros of genetic engineering
- increases crop yeild
- increased nutritional value
- can grow in harsh enviroments
-disease/herbicide/insecticide resistant crops
give 5 cons of gentic engineering:
- ethical issues
- long time side effects unknown
- can result in super weeds
- DECRESE BIODIVERSITY
- distrupts foodwebs/foodchains
why do gardners use the plant cutting method?
produce many identical clones of a parent plant
what is the method when taking cuttings?
- a shoot is cut from a parent plant [that has desired characteristics]
- end of pland shoot coated in auxin[plant hormone]
- cuttin gplaced in moist soil
- grows into clone of parent plant
give 2 reasons why tissue culture is important:
- preserve rare plant species/risk of extinsion
2.clone very large numbers in a small space = commerical
give 4 benefits of tissue culture:
- high sucess rate
- clones retain desired characteristics
- plants are free from disease
- can grow in all seasons