In Vulval Development in Caenorhabditis Elegans (A Soil Nematode), the Progenitor

question 90

Multiple Choice

In vulval development in Caenorhabditis elegans (a soil nematode) , the progenitor cell nearest to the anchor cell is exposed to the highest concentration of epidermal growth factor and activation of its EGF receptor promotes type 1 cell differentiation. The type 1 cell then prevents type 1 differentiation in adjacent progenitor cells, a mechanism called:

• A)lateral inhibition.
• B)hierarchical control.
• C)combinatorial control.
• D)downstream element inhibition.
• E)loss-of-function mutation.

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Definitions:

Genomic Imprinting

The instance when the expression of a gene is determined by whether it is inherited from the mother or father.

Crossing Over

The process during meiosis in which homologous chromosomes exchange portions of their DNA, leading to genetic recombination.

Heritability

The statistic that indicates the extent to which variation of a certain trait can be traced to genes.

Mutation

A change in the DNA sequence of an organism's genome, which can lead to genetic variation and sometimes result in observable changes in the organism.