Question 7(Multiple Choice Worth 2 points) (03.05 MC)
When an action potential reaches a neuromuscular junction, which of the following will happen first?
Acetylcholine binds to acetylcholinesterase and depolarizes the cell.
Sodium ion gates and potassium ion gates open at the same time.
Acetylcholine enters into the synapse to bond with receptor proteins.
Vesicles containing acetylcholine fuse with the presynaptic membrane.

Next pretest: evolution select the correct answer in a laboratory population of flies, the female flies are gray and the males are yellowish gray. biologists observed that all the male flies had an equal chance for reproduction, but the male flies with the brightest colors were more likely to successfully reproduce. what phenomenon could explain such a change? a sexual selection b. disruptive selection c. stabilizing selection d. directional selection

Each pair of clay balls represents two planetesimals. if each planetesimal is composed of the same material and is separated he the same distance, which pair experiences the frayed gravitational attraction?

Which of the following is an effect of the uneven heating of the earth by the sun? a sea breeze a land breeze a convection current all of the above