The term _____________ refers to a membrane that allows some things to pass through it, but not others.

A solution is a mixture of two or more substances that are physically blended but not chemically combined.

The constant appearance of new strains of influenza virus is an example of __________.

Which letter represents the effectorof this feedback loop?

What level of structural hierarchy is represented by the letter E?

A solution that resists a change in pH when an acid or base is added to it is a(n) __________.

An enzyme issubstrate-specific because of the shape of its __________.

What is the study of the structure at E called?

Which of these has the highest H + concentration?

What is indicated by the arrow?