When a planet, in its orbit, is closer to the Sun, it:

In Newton’s Law of Gravity, the force of gravity goes up as the:

The planet in our solar system with the shortest period of revolution is:

If there really were a Santa Claus at the North Pole, what would the cycle of the seasons be like for him and Mrs. Claus?

In Ptolemy’s system the planets orbit the Earth and not the Sun. How did the system explain the retrograde motion of planets like Jupiter?

The point in the sky directly above your head at any given time is called the

Below is a recording of the Vm in a postsynaptic neuron. How would you best describe the region within the brackets (marked with an asterisk(*))? 

Transmitter-gated ion channels have a similar structure, with each subunit containing 

Which toxin causes paralysis through buildup of ACh at the neuromuscular junction (NMJ)?

Which correctly describes the status of the voltage-gated K+ channel during the falling phase of an action potential?