i just have a doubt in genetics...okay so according to the independent assortment, the inheritance of a trait is independent of the inheritance of another...
so in an example, when we are talking about corn kernal coulour and texture, does the expression and inheritance of colour have to do anyhting with texture and vice versa?
so in an example, when we are talking about corn kernal coulour and texture, does the expression and inheritance of colour have to do anyhting with texture and vice versa?
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I would think that texture is a separate trait from color, so it would be determined by a different pair of alleles. Whether the corn is white or yellow is different from whether it is rough or smooth; the two traits are independent from each other.
This is like tallness vs short plants and wrinkled vs smooth pods in pea plants; they are different traits carried by different alleles.
This is like tallness vs short plants and wrinkled vs smooth pods in pea plants; they are different traits carried by different alleles.
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Well I guess it's more like a rule of thumb ;)
The law of independent assortment is true as long as the two (or more) genes in question are on *different* chromosomes.
If they are positioned on the same chromosome a phenomenon called linkage occurs where two traits are inherited together more often that by chance (ie more often than 50%).
To get back to your example: If the genes for kernel colour (eg yellow and white) and texture (eg hard and soft) are on different chromosomes the 4 different combinations should occurs about 25% of the time each in the F2 generation. But if the genes are on the same chromosome, "yellow and hard" and "white and soft" may be more likely than "yellow and soft" and "white and hard". Does that make any sense?
The law of independent assortment is true as long as the two (or more) genes in question are on *different* chromosomes.
If they are positioned on the same chromosome a phenomenon called linkage occurs where two traits are inherited together more often that by chance (ie more often than 50%).
To get back to your example: If the genes for kernel colour (eg yellow and white) and texture (eg hard and soft) are on different chromosomes the 4 different combinations should occurs about 25% of the time each in the F2 generation. But if the genes are on the same chromosome, "yellow and hard" and "white and soft" may be more likely than "yellow and soft" and "white and hard". Does that make any sense?