Question

The defining characteristics of active transport are that this category of transport moves substances _________ their concentration gradient and requires ___________.

Answer 1

Answer:

Against; energy.

Explanation:

1. Active transport is the transport of molecules, in that the particles move across a membrane from a region of lower concentration to a the region of higher concentration with the help of energy.

2. Active transport is the energy-requiring process and results in the transportation of molecules and ions across membrane against a gradient called uphill transport.  

3. Example: The Sodium-Potassium pump.