Neuronal Receptors

A neuroscientist is studying a rare genetic disorder that causes neurons to develop without their characteristic branch-like extensions that serve as the primary input sites. As a result, these neurons are unable to effectively receive messages from neighboring nerve cells. Which specific component's malformation is the most likely cause of this communication failure?

A neuroscientist observes that a specific neuron is effectively transmitting signals to other neurons, but it fails to respond to signals sent from other neurons. This suggests a malfunction primarily related to which of the following functions?

Dendritic Branching