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.
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Answer:
Some animals have camouflage which helps them not get eaten.
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(of an immature or stem cell) capable of giving rise to several different cell types.
        
             
        
        
        
Darwin's plans to find out about simulated choice by examining pigeons is that he needed to learn whether you can change the entire species taking after that particular pigeon into another type of pigeons. I hope the answer will help you. 
        
             
        
        
        
No, sometimes recessive genes come from extended family, Hope it helps!