Question

match the traits with examples of how they influence the phenotype of an organism. environmental effects epistasis pleiotropy chickens will produce a “walnut comb” on their head only if they possess at least one dominant allele in each of two different genes. a gene influences both the height of a tree and the number of branches that it produces. fish will only grow colorful tails if no predators are present during development.

Explanation:

Epistasis is when one gene's expression is affected by one or more other genes. Pleiotropy is when a single gene influences multiple traits. Environmental effects are when external factors impact phenotype. Chickens' comb - epistasis as it depends on two genes. Tree's traits - pleiotropy as one gene affects multiple traits. Fish's tail - environmental effects as it depends on predator presence.

Answer:

Chickens will produce a "walnut comb" on their head only if they possess at least one dominant allele in each of two different genes - epistasis
A gene influences both the height of a tree and the number of branches that it produces - pleiotropy
Fish will only grow colorful tails if no predators are present during development - environmental effects