Question

1. dominant alleles are not better than recessive alleles.

the term dominant allele has nothing to do with whether an allele is better. take rock pocket mice,
where fur color is controlled mainly by a single gene.
the gene codes for a protein that makes dark
pigment. some rock pocket mice have dark fur, and
some have light fur. the dark - fur allele is dominant,
and the light - fur allele is recessive.
when mice live in a habitat filled with dark rocks, dark
fur is \better\ because it makes the mice less visible
to predators. but when mice live in a habitat filled with
light rocks and sand, light fur is \better.\ its the
environment that matters, not whether the allele is dominant or recessive.
exit ticket
why do only some inherited genes become traits seen in the offspring?

Explanation:

Genes can be dominant or recessive. Dominant alleles are expressed if present (even in heterozygous state), while recessive alleles are only expressed when two copies (homozygous recessive) are inherited. So, if a gene is recessive and the offspring has only one copy (heterozygous), that trait won't be seen. Also, some genes are not expressed due to gene regulation (e.g., certain genes are turned off in specific cells/tissues). Inheritance patterns (like Mendelian genetics) and gene expression mechanisms determine which inherited genes become visible traits. For example, in the rock pocket mice, the dark - fur allele is dominant, so if an offspring inherits one dark - fur allele (and one light - fur allele), the dark - fur trait is seen; the light - fur trait is only seen if two light - fur (recessive) alleles are inherited.

Answer:

Only some inherited genes become traits in offspring because of allele dominance/recessiveness (dominant alleles are expressed over recessive in heterozygotes) and gene expression regulation. Dominant alleles show traits if present (even once), recessive alleles only show with two copies. Also, some genes are not expressed due to cellular/tissue - specific regulation. For example, a recessive allele trait appears only in homozygous recessive offspring, and dominant allele traits appear in heterozygous or homozygous dominant offspring.