What term refers to the photographic image of a karyotype?

The term that refers to the photographic image of a karyotype is "karyogram." A karyogram is a visual representation of the chromosomes in a cell, arranged in a standard format, usually by size and shape. This allows for the observation of chromosomal abnormalities, such as aneuploidy or structural changes, and plays a crucial role in genetics and cytogenetics.

In the context of karyotypes, the karyogram displays the complete set of chromosomes, providing a comprehensive overview of an organism’s genetic blueprint, which is essential in various fields including medicine, genetics, and veterinary science. It serves as a practical tool for diagnosing genetic disorders.

The other terms, while related to genetics, describe different concepts. For instance, "genotype" refers to the genetic constitution of an individual, "chromatid" refers to one-half of a duplicated chromosome, and "phenotype" describes the observable traits or characteristics resulting from the genotype. None of these terms describe the photographic representation of chromosomes, which is why karyogram is the appropriate term to use in this context.