Inheritance, Variation and Evolution 2 Flashcards
What is a mutation
A change in a base in DNA
How to name an organism using classification system (Binomial name)
Genus, Species
Who came up with the classification system
Linneaus
Binomial name meaning
Genus, Species
(How you determine the name of any organism as binomial means 2 names)
Linneaus used a classification system to group together living organisms based on what 2 things
Structure and characteristics
What advancement allowed Linneaus’s classification system to be replaced with the ‘Three Domain’ system
Technology
E.g microscopes, DNA evidence and biochemistry
Who developed the Three Domain system
Woese
Which system is used today, the classification system or the Three Domain system
Three Domain system
(It’s more advanced due to using technology e.g biochemistry)
3 categories Three Domain divides organisms into
Archaea
Bacteria
Eukaryota
What is included in the Archaea category in the Three Domain
Primitive (ancient) bacteria (live in extreme environments)
What comes under the ‘Bacteria’ category in the Three Domain
True bacteria
What comes under the Eukaryota category in the Three Domain
Animals
Plants
Protists
Fungi
Development of classification system to Three Domain system including how each system works and who came up with it
1) Linnaeus came up with the classification system: kingdom, phylum, class, order, family, genus, species
Organisms are categorised based on structure and characteristics
Organisms are named using the binomial system (genus, species) which is how you decide the name for each organism
2) Advances in technology led to Classification system being replaced with ‘Three Domain’ system which was developed by Woese
Organisms categorised into 3 categories: bacteria (true bacteria), archaea (primitive bacteria), eukaryota (plants, animals, fungi, protists)
Variation definition
Differences in characteristics between individuals in the same population
3 main causes of variation (differences in characteristics between individuals in the same population)
1) inheriting different genes e.g eye colour
2) Environment e.g language spoken
3) combination of both genes and environment e.g height can be based off genes and diet
True or false, most mutations have an effect on our phenotype
False
Most have no effect
Variation is caused by 3 things including genes, environment and combination of genes and environment
But what causes specifically genetic variation
Mutations
Very rarely a mutation leads to a new what
Phenotype
(But most of the time mutations have no effect on phenotype)
When is a mutation leading to a new phenotype an advantage (although it’s very rare that mutations actually change the phenotype)
If the environment changes
Then the new phenotype can actually be beneficial
This then leads to rapid change in a species
What does it lead to if a mutation leads to a new phenotype that can be beneficial if the environment changes
Rapid change in that species
Describe process of natural selection
1) Variation in phenotypes occur between different organisms of the same species (e.g some rabbits have thick fur, some rabbits have thin fur)
2) if the environment changes, organisms best suited to the environment are more likely to survive and reproduce (e.g if it suddenly got colder the rabbits with thick fur would be more likely to survive)
3) These beneficial characteristics are passed on to the offspring e.g thick fur
(This happens over many generations until the beneficial characteristics are widespread across the population meaning that the species has evolved)
Evolution occurs through what process
Natural selection
Evolution meaning
Change in inherited characteristics of a population overtime through the process of natural selection
4 key examples of selective breeding
1) domestic dogs have been selectively bred to have a gentle nature
2) food crops have been selectively bred to be resistant to disease
3) Animals e.g cows have been selectively bred to produce more meat and milk
4) Certain plants have been selectively bred to produce large or unusual flowers
Describe the process of selective breeding
1) select parents with the desired characteristic from a mixed population
2) Breed them together
3) Choose offspring with desirable characteristic and breed them together
4) repeat this over many generations until all offspring have desired characteristic
Fill in the gaps for key examples of selective breeding
1) domestic dogs are selectively bred to have a … nature
2) Animals e.g cows are selectively bred to produce more… and …
3) certain flowers are selectively bred to have…..or…..flowers
4) crops are selectively bred to be resistant to….
Gentle
Meat, milk
Large, unusual
Diseases
2 key problem of selective breeding
Inbreeding (breeding together closely related animals/ plants)
Causes some breeds to be particularly prone to inherited diseases/ defects
Reduces genetic variation (all of a species could be susceptible to a certain disease)
One key problem of selective breeding is inbreeding which is where…
This is bad because it can make some breeds particularly prone to…
Closely related plants/ animals are bred together
Inherited diseases/ defects
Variation is the differences in characteristics between individuals of the same…
Population
Variation is the change in ….. of a……. overtime through the process of natural selection
Inherited Characteristics
Population
What is genetic engineering
The genome of an organism is changed by introducing a new gene from another organism in order to produce a desired characteristic
Genetic engineering is where the…. of an organism is changed by introducing a… from another organism to produce a desired….
Genome
Gene
Characteristic
Another word for genetic engineering (how it is advertised in food)
Genetic modification
2 key examples of where genetic engineering is used
Crops
(to get GM crops- crops can produce bigger/ better fruits, be resistant to certain diseases, produce a higher yield etc)
To treat type 1 diabetes (bacteria contain insulin gene to produce insulin)
How is insulin produced through genetic engineering
Bacteria given human insulin gene
Bacteria produce insulin
Insulin purified and used (e.g for people with type 1 diabetes to inject insulin into themselves)
Process of genetic engineering (changing the genome of an organism by introducing a gene from another organism to produce a desired characteristic e.g larger crop yield)
1) identify gene we want to transfer
2) enzymes used to isolate gene
3) gene transferred into vector e.g plasmid
4) desired gene inserted into cells of target organism during early stage of organism development
Process of genetic engineering:
1) identify… that we want
2) use… to isolate the gene
3) transfer gene into….e.g plasmid
4) insert desired gene into cells of targeted organism using the vector
Important- this must be done during organism’s early stage of..
Gene
Enzymes
Vector
Development