Question

what is meant by phenotype;pure line;expressed character;allele

Answer 1

Phenotype refers to the difference in outer characters of any kingdom.
Allele are alternative form of genes.

Answer 2

Phenotype: Phenotype is defined as the characters which can be seen is known as phenotype
Allele: The pair of factors  which are responsible for a character is called allele
Pure line:a breed or strain of animals or plants in which certain characters appears in successive generation as a result of inbreeding or self fertilization