Information content in phenotype vs. genotype

With the human genome as small as it is(approx 3gb.), how is the genotypic expression coded(e.g. human brain's 100 billion neurons)?. The data content in the fully developed organism easily eclipses that of the genome, so that must mean this complexity, things like the interconnections between brain neurons, are emergent properties?

Correction: in the first sentence i meant to say how is the phenotype encoded.

It isn't.

In the case of neurons, the information is not encoded in the genes.

It is analogous to a computer, which doesn't come with programs installed or data loaded.

Genotypes are what's encoded, phenotypes are the physical manifestation of the genotypes depending on the environmental circumstances.

eg. genotype for big dick available but malnutrition makes for a small pug.

a lot of phenotype is just noise anyway, genotype is like lossy compression and the decompresser just makes shit up as it goes

>>1 Back to Bio I, please.

>>7
Not OP, but actually my Bio I made a huge deal out of how life (including development of an adult organism from a single zygote) in general decreases entropy (increases information) and so has to use up a corresponding amount of energy.

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