The is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.1. plasma membrane2. nucleoid region3. ribosome4. pili5. cell wall

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

As the earth formed, the force of gravity increased due to increased mass. what effect did this increased gravity have on the forming planet?

Achemical that is released by an animal as a signal to other members of the same species is called a pheromone. t or f