evolution and genetics Flashcards
evolution model answer
variation in the species and competition
best adapted survive with advantageous allelle
they breed
pass on the characteristics to net gen which ocntains more of the characteristics
following generation
How is selective breeding done
desired characteristic is identified
animals with desired characteristic breed
only the offspring with the desired characteristic in there phenotype are allowed to breed
repeated over many generations until phenotype is established
reasons for selectively breeding animals
flavour
size
aesthetic
selective breeding in plants adv/disadv
adv can increase yield can breed for disease resistance disadv usually involves inbreeding recessive diseases are more common.
selective breeding in plants process
select tomatoes with that characteristic of large tomato. Collect pollen of desired plant and then collect pollent from plant and transfer to stigma of the plant. cover selected pants to prevent cross pollination, male gamete will fuse with female gamete in ovule. wiat ofr seeds to develop, collect and plant seeds. Allow seeds to grow, selct large tomato producing offspring and allow these to grow, repeat over many generation.s
key definitions
transgenic
restriction
vector
an organism that contains dna from a different species
an enzyme that cuts DNA at a certain site
a mechanism for transferring genetic material into the chromosomes of a cell in genetic engineering such as a virus or a bacterial plasmid.
dna ligase
genetic engineering
recombinant
enzyme that joins dna together
removal of a gene from an organism and the insertion into another organism of a different species so that the gene is expressed.
genetically modifying bacteria as a vector
cells that produce desired protein is identified
desired gene is cut using a specific restriction enzyme
plasmid vector dna is cut open using the same restriction enzyme
cut plasmid and desired gene are joined together using a ligase enzyme to form recombinant dna
then inserted into another bacterial cell
this will produce the desired protein
bacteria grown in a fermenter
genetically modifying animals
genetically modifying animals
cell that produces desired protein is removed
desired gene is cut using restriction enzyme
gene is inserted using a specific restriction enzyme
gene is inserted into an egg cell joined using ligase
egg is implanted into a surrogate and allowed to develop as nomal
every cell in the transgenic offsrping will have inserted gene
how can mutation affect the phenotype change in a base sequence
how can mutation affect the phenotype change in a base sequence
different mRNA is formed during transcription
a different sequence of amino acids will form
this will fold into a different 3d shape of protein
potentially not function resulting in a different phenotype.
what is a mutagen
soemhting that increases the likelihood of a mutation occuring, these include
ionising radiation
chemical mutagens sich as chemicals in tobacco.
process of micropropagation
plant with desirable characterisitc is identified
small pieces called explants are scraped
the explants are sterilised to kill any micro-organisms.
places on a nutrient jelly on a petri dish
cells divide by mitosis and grow into a small plant
when the plant is big enough they can be taken from the small plant if more are required.
cloning animals
remove nucleus from a non sex cell
enucleate an egg cell
electrically stimulate them to fuse them in vitro
cell will undergo mitosis until form an embryo
implant it into the womb
variation
genetic variation caused by genes
caused by environment and genetics
