which group of organisms includes species that can directly transfer gametes from one individual to another through external genitalia

Johnny rode his bike to a friend's house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was not able to play. what was his displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point

Me the formula cacl2 represents the compound

Which statement best describes how the nucleus, the rough endoplasmic reticulum, and ribosomes interact during protein synthesis?