// Topic 4 Flashcards
describe the reasons why the anatomy of the pentadactyl limb suggests that bats and cats evolved from a common ancestor
same structure of bones and the structure would be unlikely to appear more than once unless a common ancestor is shared
genetic analysis also provides evidence for evolution. scientists can sequence genes from different organisms.
describe how this type of genetic analysis provides evidence for evolution
you can compare the genes of different organisms and closely related organisms have similar sequences
give one reason why the three domain classification system was proposed
genetic analysis
birds are classified in the domain Eukarya.
why are the cells from birds described as eukaryotic?
A) they have membrane bound organelles
B) they do not have nuclei
C) they have a rigid cell wall
D) they have a cell membrane
A) they have membrane bound organelles
yeast cells can be genetically modified to produce a painkiller. one method involves modifying a yeast cell using a plasmid containing the desired gene
explain how a gene can be inserted into a plasmid
cut the plasmid and gene out with a restriction enzyme and insert the gene into the plasmid using ligase. the gene and plasmid have the same sticky ends
what are the benefits and risks of producing painkillers from genetically modified yeast cells rather than extracting the painkillers from poppies
yeast grows rapidly therefore it increases yield and it can be produced in a shorter time period however the painkillers may not be as effective
colistin is an antibiotic used to treat infections in the bloodstream. some bacteria are resistant to colistin.
explain how these bacteria have become resistant to colistin
people don’t finish their course of antibiotics so evolution occurs and some bacteria have a mutation. these resistant bacteria survive and reproduce
organisms scan be classified by the five kingdom or three domain method. what is the name of the domain that plants belong to?
A) eukarya
B) archaea
C) monera
D) protista
A) eukarya
plant cells contain chloroplasts. what happens in a choroplast?
A) oxygen produced, sunlight absorbed by chlorophyll
B) carbon dioxide produced, sunlight absorbed by mitochondria
C) oxygen produced, sunlight absorbed by mitochondria
D) carbon dioxide produced, sunlight absorbed by chlorophyll
A) oxygen produced, sunlight absorbed by chlorophyll
give a reason why the three domain method of classification has been suggested
improved genetic analysis
figure 8 showing a plasmid containing the human insulin gene.
explain how the human insulin gene can be inserted into a plasmid
cut the gene from the genome using restriction enzymes as well as the plasmid. this leaves sticky ends. you can then join the DNA using ligase
scientists think that great tits living now have longer beaks because of the increased use of bird feeders during the last 50 years.
explain how natural selection could have caused an increase in beak length because of the use of bird feeders
the population of great tits shows variation. the birds with longer beaks can get more food therefore these birds are more likely to survive and reproduce. over many generations the beak length of the bird population increases
