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please help! (1 Viewer)

razzle_red

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please help! need answers today!

my teacher gave us a list of dot points to answer, and i dont have the book. i dont know how to answer this one:


  • outline ways in which the environment may affect the expression of a gene in an individual

i also have a problem with why the inheritance of sex-linked genes and alleles that exhibit co-dominance do not produce simple Mendelian ratios.

help please ! :confused:
 
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smurfus

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Environmental factors can effect the phenotype of an individual for example Siamese cats have black tips of feet tail and ears because they are colder regions of the animal. This was proved experimentally by scientists who attached cold pack to kittens and those area also went black after a long time

Another example of the influence of the environment on the appearance is the height of plants. Genetically identical plants will grow to different heights if they are exposed to different growing conditions.

Co-dominance doesn't produce simple mendellian rations because the offspring that are heterozygous (have a dominant and recessive allele) dont display the dominant phenotype. Whereas the mendellian ratios depend on that.

Sex-linkage also wont produce the mendellian ratio in males because they only recieve one copy of the allele not two.
 

Timothy.Siu

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i think i learnt about some plant hydrangeas or something that shows different colours depending if the soil is acidic or alkaline.
 

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