a breed of domestic chicken can have black grey and white write down the genotypes produced by black white and grey allele
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Answer:
If you breed poultry or are considering breeding poultry, a basic knowledge of poultry genetics is important. In particular, it is useful to understand the key elements of genetics and to know why certain traits exist in certain chickens.
A basic knowledge of poultry genetics begins with understanding the following key terms:
DNA (short for deoxyribonucleic acid)—The material containing the genetic instructions used in the development and function of an organism. DNA is arranged in double helix–shaped strands.
Gene—A segment of DNA that carries a blueprint for the function of a cell and, ultimately, a particular characteristic of an organism.
Chromosome—A structure containing a complete strand of DNA. Chromosomes function in the transmission of hereditary material from one generation to the next. Chromosomes typically come in pairs, with one set donated from the mother and one from the father. Humans have 23 pairs of chromosomes. Chickens have 39 pairs.
Genotype—The genetic makeup of an organism.
Phenotype—The observable physical or biochemical characteristics of an organism resulting from its genotype. Examples of aspects of a chicken’s phenotype include body shape, feather color, eye color, comb type, and so on.
The two categories of chromosomes are sex chromosomes and autosomes. The sex chromosomes carry the genetic material that determines the sex of an offspring. In humans, the sex chromosomes are referred to as X and Y. A human having the sex chromosomes XX is female, and a human having the sex chromosomes XY is male. In chickens, the sex chromosomes are referred to as Z and W. A chicken having the sex chromosomes ZW is female, and a chicken having the sex chromosomes ZZ is male. The sex chromosomes of mammals and birds are illustrated in Figure 1. Autosomes are all the chromosomes except the sex chromosomes.