Assistant Laboratory Animal Technician (ALAT) Practice Exam

What term describes an animal's observable characteristics including its physical appearance and internal physiology?

1. Genotype

2. Phenotype

3. Allele

4. Chromosome

The correct answer is: Phenotype

The term that describes an animal's observable characteristics, including its physical appearance and internal physiology, is phenotype. This encompasses a wide array of traits, such as size, color, shape, and any detectable emotional or behavior patterns, as well as internal characteristics like organ structure and function. The phenotype results from the interaction between the genotype (the genetic makeup) and the environment, allowing scientists and researchers to study how external factors can influence observable traits. Genotype, on the other hand, refers specifically to the organism's genetic constitution, which is not always directly observable. Alleles are various forms of a gene that can exist at a specific locus on a chromosome, and chromosomes are the structures that contain and organize genes within the cell. While these terms relate to genetics, they do not encompass the broad scope of visible characteristics that phenotype does.