Practice paper reflection Qs- DIVERSITY Flashcards
Do membranes provide support for the cell
No
Changes resulting from gene therapy cannot be passed on to offspring
True or False
False, they can be
How many out of
mitosis
meiosis
Apoptosis
are important in determining the body plan of an organism
Mitosis
Apoptosis
(not meiosis)
can pathogen transmission through droplets happen in plants
no
Explain why typical phenotypic ratio might change due to Autosomal linkage
-Both genes occour on same chromatid
-No independant assortment
-so alleles inherited together / end up in same gamete
-(unless) crossing over occours / chiasma forms between gene loci
Y allele codes for a functioning enzyme
y allele codes for an inactve form of this enzyme
Explain why the y allele is recessive
(active) enzyme will still be synthesised even if you only have one Y allele
What does a slight change in homeobox genes tell us about the classification of two Animals
-Very little as homeobox genes are highly conserved within kingdoms
-Only tell us that they belong to same kingdom
Why don’t you grow bacteria in schools at 35°C
Could encourage growth of human pathogens
How do repeats improve an investigation
-reduce impact of anomolous results
-measure /ensure repeatability
-allow calculation of standard deviation/ named stats test
- mean more likely to be accurate /closer to true value
Explain why genetic bottleneck can lead to low genetic diversity (2mrk)
-alleles lost
-modern pop descended from few survivers
Explain why genetic drift is likely to be of particular concern in the population of 100 cheetahs in Iran
-one Indiv has proportionally higher effect on small population
-(more likely) alleles will be lost from pop.
-(pop.) more likely to become extinct due to Environmental change
How to work out nunber of possible variations of genetically different gamete if independant assortment is the only source of genetic variation
2^n.
Where n is the number of haploid chromosomes
why is accurate classification of organisms important
when classifying subspecies
-Ensures subspecies do not go extinct
-allows clear communication between scientists
-allow scientists to better understand evolutionary relationships
First DNA is extracted from sample tissue
Outline subsequent steps of producing DNA profile
-amplify DNA with PCR
-cut/digest with restriction enzyme
-separate using gel electrophoresis
transfer to paper/nylon
-add fluorescent probe
-use UV light to view
outline process of primary succession.
state general principles
Pioneer community
* begins with bare rock
* arrival as seeds or spores
* pioneer species have certain adaptations,
e.g. nitrogen-fixation
Intermediate community
* herb species, including grasses
* followed by shrubs and trees
Climax community
* dominance by a few tree species
* little change over time
General principles
* seral stages
* community and decomposition changes
composition of soil
* increased organic, nitrate or water content
