Atest cross can be used to -predict the phenotypes of a monohybrid cross -predict an unknown genotype of a purebred dominant plant -cross-breed dominant and recessive plants -give probabilities that a trait will appear

- Predict an unknown genotype of a purebred dominant plant.

Explanation:

The genetic make up of the organism is called as the genotype. It describes the form of genes or allelic forms present in the organism. A test cross is used to determine the genotype of the organism. In this cross the organism with the unknown genotype is done with that of the organism with the known genotype. It also determines the fact that the organism is either homozygous dominant or hetrozygous.

On the basis of the above description, Predict an unknown genotype of a purebred dominant plant.

answer: - b cells

explanation: -

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.