Describe female hetrogamy and its types .
Heterogametic Females :

Explanation

In this method of sex determination , the homogametic male possesses two .X. chromosomes as in certain insects and certain vertebrates like fishes , replies and birds producing a single type of gamete , while females produce dissimilar gametes . The female sex consists of a single .X. chromosome or one .X. and one .Y . chromosome . Thus the females are heterogametic an produce two types of eggs . Heterogametic females are of two types , ZO - ZZ type and ZW - ZZ type .
ZO - ZZ type .
This method of sex determination isseen in certain moths , butterflies and domestic chickens . In this type , the female posses ses single .Z. chromosome in its body cells and is hetrogametic (ZO) producing two kinds of eggs some with .Z. chromosome and some without .Z. chromosome , while the male possesses two .Z. chromosomes and is homogametic (ZZ) .

ZW - ZZ type
This method of sex determination occurs in certain insects (gypsy moth ) and in vertebrates such as fishes , reptiles and birds . In this method the female has one .Z. and one .W. chromosome (ZW) producing two types of eggs , some carrying the Z chromosomes and some carry the W chromosome . The male sex has two .Z. chromosome and is homogametic (ZZ) producing a single type of sperm .