selective breeding booklet

Question 1

what is selective breeding

Answer 1

process by which humans breed plants/animals for specific characteristics

Question 2

what does selective breeding ensure

Answer 2

genes for a specific characteristic remain in the population

Question 3

give 4 reasons why selective breeding may be done:

Answer 3

• make diesease resistant crops
• animals that profucemore meat or milk
• grow large/unusual flowers
• breed gentle dogs

Question 4

explain they process of selective breeding:

Answer 4

• 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

Question 5

how can you selectively breed plants

Answer 5

• desired characteristic in plant identified the pollen [male gamete]
• placed kn the stigma of another plant w desired characteristics
• collect seeds / offspring plants
• repeat

Question 6

what are the 3 main problems with selective breeding?

Answer 6

• reduction in gene pol
• inbreeding can result in health problems
• new diseases and defect can occur

Question 7

why is a reduction in gene pool bad

Answer 7

• number of different alleles in population decrease
• alleles w non desired characteristics can be lost
• all off spring = inbred

Question 8

how can inbreeding result in healthy problems

Answer 8

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

Question 9

how can new diseases form w selective breeding

Answer 9

reduces genetic variation

Question 10

what does genetic engineering involve

Answer 10

MODYFYING THE GEONOME of an organism by introducing a gene from another organism to give a desired CHARACTERISTIC

Question 11

give 2 times generic engineering is used:

Answer 11

• make plants resistant to disease / produce bigger plants
• bacteria cells GM to produce human insulin

Question 12

what does transgenic mean

Answer 12

when organism have been given genes form other organisms

Question 13

what is the method for genetic engineering

Answer 13

• 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

Question 14

name 4 examples of genetic engineering:

Answer 14

• TREATING DIABETES
• GENETICALLY MODIFIED CROPS
• GENERICALLY MODIFIED SHEEP
• GENE THERAPY

Question 15

how can GM test diabetes

Answer 15

bacteria have been GM to produce human insulin for diabetics

Question 16

how is GM usefull for crops

Answer 16

increase yield, increase size, quality, disease/herbicide RESISTANT

Question 17

why is GM sheep good

Answer 17

produce specific substances in their milk

Question 18

why is GM good for gene therapy

Answer 18

GM treatments for people with inherited diseases

Question 19

what are the 4 pros of genetic engineering

Answer 19

• increases crop yeild
• increased nutritional value
• can grow in harsh enviroments
  -disease/herbicide/insecticide resistant crops

Question 20

give 5 cons of gentic engineering:

Answer 20

• ethical issues
• long time side effects unknown
• can result in super weeds
• DECRESE BIODIVERSITY
• distrupts foodwebs/foodchains

Question 21

why do gardners use the plant cutting method?

Answer 21

produce many identical clones of a parent plant

Question 22

what is the method when taking cuttings?

Answer 22

• 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

Question 23

give 2 reasons why tissue culture is important:

Answer 23

1. preserve rare plant species/risk of extinsion
   2.clone very large numbers in a small space = commerical

Question 24

give 4 benefits of tissue culture:

Answer 24

• high sucess rate
• clones retain desired characteristics
• plants are free from disease
• can grow in all seasons

Question 25

explain the method of tissue culture

Answer 25

• a block of tissue is removed from plant & sterilized
• tissue is cultivated on dishes
  -1:1 auxin & cytokinin form undifferntiated CALLUS
• 10:1 auxin & cytokinin cause root development
• then less that 10:1 auxin and cytokinin causes shoot development

Question 26

why might farmers use animal cloning

Answer 26

• increase yeild
• volume of milk
• quality of meat

Question 27

what is the method for animal cloning[embryo transplanting]?

Answer 27

• splitting cells apart at a VERY EARLY STAGE [not specialised yet]
• cells are spertaed and grown in vitro = embryo’s develop
• identical embryos impnated into surrogates
• surrogate’s offspring will all be gentically identical

Question 28

explain the method of adult cell cloning?

Answer 28

sheep 1
- adult cell that wants to be clones [desired characteristics]
-adult cell has its NUCLUES[DNA] removed from cell
sheep 2 - female sheep
- egg cell is taken
- ovum cell is ENUCLEATED

[put together] + ELETRIC SHOCK - stimulates egg cell to divide by MITOSIS = embryo
- embryo is inserted into surrogates womb and off spring = cloned sheep 1

Question 29

give 2 pros of cloning techniques

Answer 29

• prevent extinsion of species
• ## increase yeild

Question 30

give 3 cons of cloning techniques

Answer 30

• ethucal issues
• reduce in gene pool/ varaiation
• decreses biodiversity