The physical expression of genes are phenotype. Phenotype is the expression of the gene by the appearnace of the organism. It is the characteristics of that trait.
Examples : When pigment is made in our eyes, height ( tall and short) , weight, blond hair is the phenotype for the blond hair genotype and skin colour( black, white ) is the phenotype trait.
C) when the length of day and the length of night are the same
Answer:
Biology is the study of life, while physics are the study of matter and energy used to determine how the universe behaves.