Which best describes a theory? an untested claim a well-supported conclusion a proven fact an educated guess

System of ideas used to explain something

it would lead to upper respiratory infections and pneumonia.

small, big, or no change could occur in the phenotype. it could cause something as simple as a cats ears to curl backwards or something as frighting as death. it could also occur in the protien-coding area and have an effect on that but no effect on the amino acids. what has to occur is a changing in the hox gene or the control gene.