Is not considered separate species because organisms of different breeds
can mate and produce fertile offspring.
breed
phenotype
genotype
fitness

Breed is not considered separate species because organisms of different breeds  can mate and produce fertile offspring.

Explanation:

A breed is a particular gathering of residential creatures having homogeneous appearance (phenotype), homogeneous conduct, and additionally different attributes that recognize it from different life forms of similar species. Comprehensively, various species can't interbreed and create solid, ripe posterity because of hindrances called systems of regenerative confinement.

These obstructions can be part into two classifications dependent on when they act: prezygotic and postzygotic. Generally, various species don't mate. Be that as it may, when they do, their posterity will be what are called cross breeds.

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.