Professor Marshall wants to know whether eating sweets before bedtime causes children to take longer to fall asleep. In his experiment, whether or not a sweet is given before bedtime is the ________

A shortcoming of laboratory observation is that the presence of researchers may cause participants to behave differently than they would in their usual surroundings

Indicate whether this statement is true or false.

Which pair of drugs below is known to facilitate and inhibit (respectively) the release of acetylcholine?

a. fluoxetine; nicotine b. botulinum toxin; muscarine c. botulinum toxin; black widow spider venom d. black widow spider venom; botulinum toxin e. black widow spider venom; fluoxetine