B6- evolution, natural selection Flashcards
what is the theory of evolution?
all species have evolved from simple life forms that first started to develop over 3 billion years ago.
why is evolution controversial?
religion: challenged God
insufficient evidence at the time
what is natural selection?
useful characteristics become more common in a population: causes evolution
what is evolution?
gradual change of inherited characteristic of species over time
what are the six stages of natural selection: MVCBSI
mutation
variation
competition
best suited
survival & reproduction
inheritance
what is speciation?
over a long period of time, individuals phenotype of populations of one species can become so different THEY CAN NO LONGER INTERBREED TO PRODUCE FERTILE OFFSPRING they have FORMED NEW SPECIES
what is selective breeding?
Artificial breeding
why are genetic characteristics chosen?
Usefulness or appearances
what are more specific reasons genetic characteristics chosen?
-Disease resistance in food crops
-animals which produce more meat
-domestic dogs with gentle nature
-large/unusual flowers
what is the process of selective breeding?
1- from existing population choose parents w desired characteristic
2-breed parents together
3-breed offspring again with desired characteristics
4-continuous until offspring show desired characteristics
what is inbreeding?
best animals/plants in population are closely related
what can inbreeding lead too? (2 points)
-reduce gene pool
-prone to inherited defects
what is genetic engineering?
modifying the genome by introducing gene from another organism to give desired characteristic
why do we genetic engineer?
-resistance to disease
-produce bigger & better quality of fruits
-fortified with nutrients
-increased yeild of crop = food avaliability
why do we genetically modify bacteria?
to produce useful substances such as inculin
why do we use gene therapy?
for inherited disorders
what is the process of genetic engineering? (5 stages)
1- Gene isolated from Organsim using enzymes
2- useful gene inserted into vector
3-vector inserted into cells of other organism at early stage of development
4-cells divide
5-organisms develop desired characteristic
what are the 2 components and their elements apart of genetic engineering?
HUMAN CELL: nucleus, DNA- containing desired C cut out w enzyme
BACTERIA CELL: plasmid cut with enzyme, enzyme insert human gene into bacteria plasmid
pros to genetic engineering MEDICAL?
-medical research: possibility to treat inherited disorder (gene therapy)
-produce drugs: such as insulin
cons to genetic engineering MEDICAL?
-risk of changing individuals genes
-may cause unplanted problems, resources required for developed treatments
pros to genetic engineering
AGRICULTURE?
-disease resistance
-increased yield availability
cons to genetic engineering AGRICULTURE?
-affect population of biodiversity
-effect on human health
-transplanted genes ‘getting out’ into natural environment
