Several members of the Fitzsimmons family have polydactyly, and they differ in their numbers of extra fingers and toes. Yet, certain relatives who should have extra digits don't, such as Megan Fitzsimmons. She has two children, a son with two extra fingers and a daughter with an extra toe, and her father has an extra digit on each hand and foot. Polydactyly in this family is Group of answer choices variably expressive and incompletely penetrant. pleiotropic and a phenocopy. invariably expressive and completely penetrant. dominant and recessive.

variably expressive and incompletely penetrant

Explanation:

Polydactyly is a genetic disorder characterized by limb malformation (i.e., supernumerary digits). Polydactyly is a genetically complex trait influenced by different factors, including, among others, epigenetic factors, environmental factors, regulatory genomic sequences (enhancers and/or suppressors), etc. The variable expressivity of this trait is caused by the combination of these factors. Incomplete penetrance refers to the fact that the trait is expressed in only some individuals having the genetic predisposition for this condition.

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.