Facilitated diffusion is unable to transport molecules against a concentration gradient. 

A nonspontaneous reaction is a reaction that takes place without the continual input of energy from an external source.

Where does the gluconeogenesis take place?

Solve the equation by completing the square. x2+4x+8=0{“version”:”1.1″,”math”:”x2+4x+8=0″}

The immune system mainly works based on

Find the sum or difference.  Write the answer in standard form. -5+2i+8-6i-2i{“version”:”1.1″,”math”:”-5+2i+8-6i-2i”}

Multiply or divide, as indicated.  Simplify the answer. -45-5{“version”:”1.1″,”math”:”-45-5″}

_________ sources of water pollution are relatively easy to monitor and regulate, while _____________ sources of water pollution are difficult to monitor and clean up.

Approximately __________ of all energy produced is not used for an energy service.

The following diagram represents ____