How do carrier proteins recognize substances to transport in active transport? a. they will allow any substance to pass. c. they have a pore that only the substance will fit through. b. they have a specific binding site for the substance. d. the substance recognizes the carrier protein.

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?

Can a trait be both polygenic and have multiple alleles? explain why or why not.

Which of the following is a responsibility of a scientist