When Lucifer yellow, a small dye, is injected into a neuron of the retina, neighboring neurons become rapidly labeled. If the retina is incubated in dopamine prior to Lucifer yellow injection, only the injected neuron becomes labeled. These findings suggest which of the following?

I. Neurons of the retina communicate via gap junctions.

II. Dopamine is transferred between cells via gap junctions.

III. Dopamine decreases the permeability of gap junctions.

TLS Online TPP Program

#Question id: 4322

#Unit 3. Fundamental Processes

If a particular operon encodes enzymes for making an essential amino acid and is regulated like the trp operon, then

TLS Online TPP Program

#Question id: 546

#Unit 1. Molecules and their Interaction Relevant to Biology

Enzymes are potent catalysts because they:

TLS Online TPP Program

#Question id: 11138

#Unit 7. System Physiology – Animal

The point of connection between two communicating neurons is called the ________.

TLS Online TPP Program

#Question id: 11982

#Unit 10. Ecological Principles

Which of the following is a behavioral pattern that results from a proximate cause?

TLS Online TPP Program

#Question id: 15766

#Unit 5. Developmental Biology

 If a stem cell divides symmetrically, results