topic 4: natural selection and genetic modification Flashcards
Define evolution
a change in on or more characteristics of a population over a long period of time
how could you tell how old fossils are
.where it is located down in the ground (the deeper the older)
define species
a class of things of the same kind and with the same name
how do tools change from the oldest to the newest
they become more sharp, they more whittled down and more blade like
How does the development of tools sh0ows human evolution
It shows they are able to process their tools and create them into useful tools that fit their needs.The increase in sophistication of human tools over time shows the increase in human mental capacity.
what could be carbon dated
something made of living things
what is the term evolution
the change in the characteristics or appearance of an organism over a long period of time
what is a pentadactyl limb
limbs with 5 digits, suggesting evolution from a common ancestor
Keep ponds clean or ponds get sick
Kingdom
Phylum
Class
Order
Family
Genus
Species
define classification
the organisation of living things into groups according to their similarities
how does classification help us to do
allows us to see how different groups of living things are related
enables scientists to recognise the biodiversity present in the world and give scientists a common language in which to talk about
what is the taxonomy order
Kingdom
Phylum
Class
Order
Family
Genus
Species
what are the 5 kingdoms
Animals
plants
fungi
protoctista
prokaryotae
what is a saprophytic feeder
living organisms that feed on dead or decaying organisims
what is a heterotrophic feeder
an organism that eats other plants or animals for energy and nutrients
What is a autotrophic feeder
organisms that produces its own source of nutrients and energy
what is a protoctista
Mostly unicellular ( a few multicellular), complex cell structure with nucleus.
what are the different domains?
Bacteria
Archaea
Eukarya
what is the binomial system
Genus + Species
define an Archaea
2 bullets
one of the three domains
prokaryotic with no non coding sections of DNA
define Bacteria
(relateit to the classification system)
.one of the three domains
.cells with no nucleus, no unused sections in genes
define a Eukarya
.one of the three domains
.cells contain a nucleus, has unused bits of DNA
what is selective breeding
choosing the type of organisim to breed and then selecting which offspring to breed
what type animal is an example of selective breeding
domestic dogs
what are the two different types of selection
.natural selection
.artificial selection
describe selective breeding (4marks)
Selective breeding involves choosing parents with desired characteristics from a mixed population
they are bred together
from the offspring those with the desired characteristics are bred together
this continues over many generations until all the offspring show th desired characteristics
what are some selective breeding applications (at least 3 )
.disease resistance in food crops or garden plants
.animals that produce more meat or milk
.gentle temperament
.brightly coloured, large, heavily scented flowers
what are the 3 domains
the Archaea, the Bacteria, and the Eukarya.
what are the 6 kingdoms
Archaebacteria, Eubacteria, Protista, Fungi, Plantae, or Animalia
What species was the oldest
Ardi-Ardipithecus species
what were some aspects of Lucy
.chimpsized brain
.walked up right
.larger toes for climbing
why do we want to genetically modify organisms
.change the appearance
.make it cheaper
.develop it for specific use
what is a ligase enzyme
used to join sections of DNA together
what is a plasmid
a circular section of DNA found in bacteria
what is a restriction enzyme
used to cut a section of DNA from a longer strand
what is a vector in genetic engineering
used to transport DNA
what are some advantages of genetically mortified crops
.scientists have engineered them to have longer shelf lives
.foods can be engineered to grow in harsher conditions (low water supply, lower temperature) this increases crop yield and prevents malnutrition in certain places in the world
.
where does the Bt toxin gene come from?
Bacillus thuringiensis bacterium
what is biological control
using predator organisms to kill problem organisms such as weeds or pests
what are some advantages and disadvantages of using biological control
Advantages
.its natural and avoids the use of pesticides
.self sustaining
.cheap after start up
.works most the time
Disadvantages
.can disrupt the food web
.can be a slow process
.expensive at start up
.doesn’t completely destroy a pest
.it may fail in its specificity
what is a herbicide
weed killer
what are Fertilisers made of (NPK)
fertilisers contain mineral ions, such as nitrogen, potassium and phosphorus.
what do fertilisers do
The plants absorb from the soil to make healthy new cells. Fertilisers help us to increase the growth and yield of crop plants
what is recombinant DNA
DNA made by joining two sections of DNA together
what is a sticky end
short section of single stranded DNA at the end of a piece of DNA that has been cut by a restriction enzyme
what is a restriction enzyme
enzyme that cuts DNA molecules into smaller pieces used to genetically modify bacteria
benefits of genetic engineering (3 or more)
.useful in medicine, can mass produce important hormones (insulin etc…)
.introducing modifications in crops can allow them to grow under different or more extreme conditions (this can increase crop yield and so help combat famine in some places)
.crops with more vitamins can benefit countries with malnourishment
.can help plants to produce their own herbicide/pesticides.
risks/negatives of genetic modification
.don’t know the impact of eating GM crops on human health
.could lead to genetic modification of humans (designer babies)
.GM plant seeds are expensive
.may reproduce with wild flower/weeds and pass on their resistance gene making them hard to kill.
how was BT bacteria used to improve crop resistance (pros and cons)
what it is, what they did, how it helps and how it doesn’t
.BT bacteria produces toxins that kill insect larvae if ingested
.the toxin was introduced into plants so that all cells in the plants would produce this
.it was beneficial as it only effected insects that bit chew the plant tissue, whilst being harmless to insect predators (spiders ect…)
.however some pests such as aphids that suck on the sap are unaffected.
what is a monoculture
large area of crop of one type
why is growing crops in monoculture in a greenhouse advantageous
all plants are of the same type and so need the same conditions which are easy to control in a greenhouse
what is Darwin’s theory of evolution by natural selection
species evolve over time through a process of natural selection, where individuals with advantageous traits are more likely to survive and reproduce.
what are the five stages of Darwin’s theory
.Genetic variation: occurs in an individual due to differences in genes
.Environmental changes: occurs possibly causing more interspecies competition for resources
.Natural selection: the variations of some individuals make them more suited to the change that other, increasing chances of surviving to reproduce
.Inheritance: survivors reproduce and pass on their favourable allele/characteristic to their offspring, so the next generation has more individuals with ‘better adapted variations’
Evolution: natural selection occurs over and over again and eventually a new species evolves all possessing the favourable variation.
