If the cell membrane were not selectively permeable, then unwanted substances would transfer through instead of being blocked out. Think of it like this: you have a sifter with various sizes of spice in it. You only want the finer grains of spice in your food, so when you shake the sifter, the larger pieces of spice don't fit through the small holes that only allow fine grains. Then you are left with the small spices in your food and the large ones stuck in the sifter.
Hopefully this helps and I wasn't too confusing :)
Answer:
true
decomposers break down organisms and return the carbon in their bodies to the atmosphere.
Answer:
The term nucleic acid is the overall name for DNA and RNA.
Explanation:
They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. ... The two main classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).