Classification And Evolution PPQs Flashcards
Use information from figure 3 to suggest why the two females did not attempt to mate (2)
Mp1 - Peaks occur at the same time because they are both female (aka. They don’t hear the three peaks of the male)
Mp2 - So no male song to stimulate
Differences in the primary structure of haemoglobin molecules can provide evidence of phylogenetic evolution relationships between species. Explain how (5)
mp1 - mutations cause change in base sequence
mp2 - so change in AA sequence
Mp 3 - mutations build up over time
Mp 4 - more mutations = more distantly related species
Mp 5 - closely related species have a more recent common ancestor. Distantly related species have an early common ancestor
NOTES
‘Differences’ = aka mutations
First 4mps = explaining how mutations cause diff relations
5th mp - like summary idek AQA is disgusting
Explain the purpose of transferring the same volume of liquid culture onto each agar plate (1)
So same number of bacteria transferred to allow for comparison.
Explain the purpose of boiling the agar. (1)
No contamination
Describe how you would obtain a more accurate estimate of the minimum concentration of antibiotic needed to stop the growth of the bacterium? (2)
Mp1 - Use values (of concentration of antibiotic) between 10 and 15
Mp2 - repeat (using) each value
Calculate the percentage difference in actual numbers of bacteria in group A compared with group R (2)
XXXX
97-97.8%
Scientists said to use the current antibiotic and the new antibiotic.
Use the graph and your knowledge of evolution of antibiotic resistance in bacteria to explain your answer. (3)
Mp1 - The new antibiotic doesn’t kill all of the bacteria
Mp2 - (Some bacteria will be resistant to the new antibiotic) these will reproduce to produce more resistant bacteria
Mp3 - Using both antibiotics means one antibiotic will kill the bacteria resistant to the other antibiotic
Write the letter M on the diagram to show where meiosis occurs (1)
Meiosis occurs during sexual reproduction when the chromosome number halves (2n —> n)
Eg. Zygote —> zygospore
Explain one advantage of a sexual reproduction and one advantage of sexual reproduction. (2)
Mp1- asexual: fewer stages so quicker/only one parent involved so can colonise new environment/produces clone so successful genotype maintained
Mp2- sexual: increases genetic diversity so more chance of survival
Suggest one advantage of the hypha being vertical. (1)
Allows spores to spread/disperse further
Describe how scientists could calculate the mean volume of spores (3)
XXXX
Measure diameter of a large number of spores
Divide measured valleys by 700 (to find true diameter)
(Add and divide true diameters by number of spores to find mean?)
Use volume of a sphere
Binomial naming system
Homo sapiens
Genus species
What does the phylogenetic tree show about the relationship between the fungi and insects? (2)
Common ancestor
Diverged a long time ago (DON’T SAY EARLY ON)
What can you conclude about the effect of hunting on genetic diversity in otters? (2)
Hunting reduced population size so only a few alleles left
Otters today from one of the surviving populations
Inbreeding
Two reasons why populations might show very low levels of genetic diversity other than hunting (2)
Genetic bottleneck
Founder affect
Explain the principles which biologists used to classify organisms into groups (3)
Large groups divided into smaller groups
Members of groups have features in common based on anatomy
Reflects evolutionary history
Suggest how information on amino acid sequences is used to construct a phylogenetic tree (2)
Closely related species have similar amino acid sequences
Greater/more differences in amino acid sequence = longer ago the groups diverged
*LONGER AGO GROUPS DIVERGED
NOT
‘More differences means more distantly related’ - say answer in terms of time.
Suggest one advantage and one disadvantage of using cytochrome C to construct a phylogenetic tree (2)
Adv - Present in all eukaryotic species of organisms/quantifiable
Dis - Extinct species can’t be considered/ prokaryotic species can’t be included/ only a limited number of amino acid sequences
Scientist want to confirm a relationship between three species.
They made samples of hyper DNA using a gene that was found in all three species.
Explain why it is important that they make samples of hybrid you know from the same gene (2)
The base sequence will be similar (related species will have some bases in common)
So complimentary base pairing and formation of hydrogen bonds can occur
DNA hybridisation
Explain what caused the DNA to separate a high temperature (2)
Two organisms have closer relationships so more complimentary bases
So more hydrogen bonds which require more heat energy to be separated
Explain how these results suggest the animal is the most closely related to humans (2)
*A only has one difference in amino acid sequence compared to cytochrome C in humans
A has the LEAST (smallest) number of differences
So base sequence must be more similar
Suggest one reason why be and say might not be more closely related to each other than any of the other animals (1)
B and C have 12 differences in am in o acids compared to cytochrome C
Differences in B and C are compared with number of differences in humans. Not compared with each other.
(Even if B and C had the same number of differences) the differences may be at different positions (hence not as closely related)
Suggest why cytochrome C is more useful than haemoglobin for studying how closely related different organisms are. (1)
All organisms respire and have cytochrome C
Cytochrome C structure is more conserved/less varied between organisms
Explain why biologists could use calls to investigate relationships between different species of crane. (2)
Calls are species specific (and allow recognition of the same species)
Greater similarity in calls the more closely related the species are
