CB4 - Natural selection and Genetic Modification Flashcards
What is evolution?
The gradual change in the characteristics of a species over time.
What were the names of all the fossils showing human evolution?
Ardi
Lucy
Homo habilis
Homo erectus
Homo sapiens
How did scientists discover human evolution?
Fossils
How did scientists discover human evolution?
Fossils
What were the changes in characteristics in the human fossils?
Facial features got smaller
Brain casing grew in size
How is human evolution seen through the tools used?
The tools got smaller and more refined.
Symbols started getting put on the tools.
How can we tell how old a fossil is?
How deep it is underground
Carbon dating
Why do scientists carbon date the rock around the tool and not the tool?
The stone or materials used to make the tool are older than the tool itself.
What is genetic variation?
Where the characteristics of individuals vary due to genetic differences and mutations or environmental change.
What is the definition of species?
A group of organisms that can reproduce with one another, producing offspring that can also reproduce.
What are the steps of natural selection?
Variation
Change in environment
Competition/ adaptation
Survival of the fittest
Inheritance
Evolution
What is the variation stage of natural selection?
Individuals look slightly different, caused by mutations.
What is the competition stage of natural selection?
Some individuals are more able to survive than others, as they are better adapted to their environment, due to variation.
What is survival of the fittest stage of natural selection?
The individuals that are more adapted survive, whereas the others die off.
What is the inheritance stage of natural selection?
The fittest individuals reproduce, and their offspring inherit the characteristics that helped their parents survive.
How does evolution occur?
When the natural selection cycle repeats.
Who invented the Kingdom classification system?
Carl Linnaeus
What were the five kingdoms of classification?
Animals
Plants
Fungi
Protists
Prokaryotes
How did the Kingdom system classify organisms?
Their structure and looks.
What are the limitations of the class system?
Looks aren’t related to genetics.
Who invented the domain system?
Carl Woese
What are the 3 domains?
Bacteria
Eukaryotes
Archea
How did the domain system classify organisms?
By genetics / DNA
How did antibiotic resistance come to?
Some bacteria have a mutation that makes it more resistant to antibiotics.
The antibiotics killed the bacteria without the resistance.
The bacteria with the resistance reproduces and their offspring inherits the resistance.
What is artificial selection?
When humans chose certain organisms because they have useful characteristics.
What are the stages of selective breeding?
Humans choose desirable traits/ characteristics.
Choose the parents that show these characteristics.
The offspring inherits this characteristic
Select the best offspring to breed the next generation.
Repeat the process.
What are the disadvantages of selective breeding?
Alleles that may be useful in the future are gone
Disease genes can lead to problems with specific organisms
Create physical problems in organisms.
What are the benefits of selective breeding?
Produces a higher yield
Produces more varieties and breeds
What is the definition of genetic engineering?
Altering the genome of an organism by adding genes from another species.
What is a genome?
All the DNA in an organsim.
What is yield?
The amount of useful product that you can get from something.
What are the stages of genetic modification?
Organism to modify is selected.
The desired gene is selected from an organism of another species.
The gene is cut out of the genome using a restriction enzyme, which also cuts the other organisms DNA.
The gene is inserted.
What is an allele?
A different version of a gene.
What are advantages of GMO’s?
Disease resistant crops
Golden rice - added nutrients
Pigs with the same organs as humans
Fish that grow larger and faster
Faster than selective breeding
What are the disadvantages of genetic engineering?
Expensive
Ethical grey area
Create herbicide resistant crops
Unintentional spreading of GMO’s
How is bacteria genetically modified to produce insulin?
Insulin gene selected from human DNA
Restriction enzyme cuts the insulin gene out of the chromosomes, creating sticky ends of DNA
Plasmid is removed from bacterial cells
Restriction enzyme cuts the plasmid, creating complementary sticky ends.
Insulin gene inserted into the plasmid with enzyme ligase
Bacteria accepts the recombinant DNA and multiplies, each time producing insulin.
What are the advantages of genetically engineering bacteria to produce insulin?
Large amounts made in a short period of time
Cheap
Suitable for vegan and specific religions.
What are the disadvantages of genetically engineering bacteria to produce insulin?
Some peoples body will reject it
What are the differences between GMO’s and selective breeding?
GMO is with different species - Selective breeding is with one species.
What are the similarities between GMO’s and selective breeding?
Humans pick out the useful characteristic.
