In immunoglobulin genes, how are V and J gene segments prevented from being recombined with another segment from the same gene?
What will be an ideal response?
Ans: Recombination occurs between consensus sequences adjacent to each gene segment. The consensus sequence consists of a heptamer and a nonamer separated by a spacer sequence; V gene segment sequences have a spacer of 23 bp, while J gene segment sequences have a spacer of 12 bp. Recombination cannot occur between sequences with the same spacer, but only between sequences with different spacers, assuring that two V segments or two J segments will not be combined.
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C. seeds
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What will be an ideal response?
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the genotype and phenotype of each parent and the son. What will be an ideal response?
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a. nucleus; ribosome b. nucleolus; smooth endoplasmic reticulum c. nucleolus; cytosol d. cytosol; nucleus e. nucleus; Golgi apparatus