What is the name for the observations and data on which a scientific explanation can be based

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes

Color blindness is a recessive sex linked human trait. if a color blind father and a mother with normal color vision have a color blind son what must be the mothers genotype? a. xn yn b. xn xn c. xn y d. xn xn

Refer to this portion of a dichotomous key to answer the question.1. (a) has a single dorsal fin  ®  5          (b) has a double dorsal fin  ®  25. (a) has a small fin on back near tail  ®  6          (b) has no fin on back near tail  ®  76. (a) has barbs near the mouth  ®  catfish          (b) does not have barbs near the mouth  ®  107. (a) tail is asymmetrical  ®  sturgeon      (b) tail is symmetrical  ®  8what would the result be when identifying a fish with a single dorsal fin, no fin on its back near the tail, and a tail that is asymmetrical? sturgeongo to step 8go tp step 2catfish. mark this and return