ok so im not going to lie genetics is my best topi atall , was wondering could anyone help me or send me links to some good websites that would guide me through these two questions
maize plants heterozygous for both characteristics were crossed. The following results were obtained:
33 coloured, wrickled
29 colourless, rounded
8 colourless , wrinkled
suggest why the results are not expected 9 : 3 : 3 : 1 ratio
B] some of the colourless rounded grains would have the genotype ccRr and some would be ccRR , explain the genmetics crosses necessary to distinguish between these genotypes?
i just need someone to guide me and i will take of ,
hope to hear from someone soon
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Please help , GENETICS :/ watch
- Thread Starter
- 27-07-2010 20:08
- Thread Starter
- 28-07-2010 20:23
its pathetic that my tutor gave me work to complete but without any background notes in order to prepare me for uni .
was hoping if anyone could give me help on this ...
5) Pure-breeding pea plants with grey seed coats and tall stems were crossed with plants with white seed coats and short stems. The offspring (F1 generation) all had grey seed coats and tall stems.
a) State suitable symbols for the alleles for colour of seed and height of stem.
b)Explain, by means of a genetic diagram, the ratios of genotypes and phenotypes you would expect if the F1 generation were self-fertilised.
c)Explain how you could find out the genotype of a plant with grey seed coat and tall stems
- 29-07-2010 01:47
How dry! Should find your answer in a standard genetics text book!
- 29-07-2010 02:00
You have a standard dihybrid cross, with white and short being the recessive alleles
a) you can put anything really lol eg G/g for grey/white and similar for the other gene
c) this is asking how do you test whether each of the characteristics is homo- or heterozygous, the answer lies in crossing the defined plant with a specific different plant, where homo- and hetero- should give you different results
- 29-07-2010 02:12
http://www.biologymad.com/ is always good
linkage between the P and L alleles and the p and l alleles. The frequency of P occurring together with L and with p occurring together with l is greater than that of the recombinant Pl and pL. The recombination frequency cannot be computed directly from this experiment, but intuitively it is less than 50%.