Answer:
Active uptake (which I think you mean active transport) is important when the concentration gradient is against that of a certain substance, so it doesn't cross the membrane through diffusion or passive transport. It is sometimes necessary if a substance needs to move across a membrane but can't do so due to electrical charge or that there is a substance on the other side of the membrane preventing diffusion.
Explanation:
Under the leadership of Mikhail Gorbachev, the doctrine of perestroika called for "<span>A. Openness in communication", since the "closed off" Soviet Tactics of the past were clearly not working by the 1980s.</span>
The Mohs scale measures D, a mineral's hardness.
Get nonperishable foods, water bottles, flash lights, blankets, things like that.
