Both plant and animal cells have membranes so whatever chemical reactions they have going inside the cell, it is regulated and maintained. Membranes help separate the internal environment from the external environment.
Hope this helps - I'm currently in cell biology so this question is interesting
Answer:
I go with C which says the dark mice are hard to be seen against the dark. Because of this the dark mice lived to reproduction age and reproduce more dark mice.
'Red shift' is a key concept for astronomers. The term can be understood literally - the wavelength of the light is stretched, so the light is seen as 'shifted' towards the red part of the spectrum.
Hope this helps.
I think the answer is D because respiration releases energy.