Which statement best describes the plasma membrane?

a. it is nonpermeable to substances outside of the cell

b. its rigidity does not allow materials to enter the cell.

c. it is freely permeable to all substances.

d. it is selectively permeable to certain substances

D) It is selectively permeable to certain substances.

Explanation:

The plasma membrane is like the military of the cell. It's function is serving and protecting the cell from it's surroundings. Composed of proteins, it is very selectively permeable. This means it allows certain types of molecules or ions to pass on through it as a active or passive transport.

The correct answer is D

Explanation:

The plasma membrane is sorta like the military of the cell. It's function is to serve and protect the cell from it's scary surroundings! Composed of proteins, it is selectively permeable. Meaning it allows certain types of molecules or even ions to pass on through it, as in active or passive transport. Hope this helps! Have a blessed day!

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."