Specialized proteins in the cell membrane regulate the concentration of specific molecules inside the cell. ... Transporters carry a molecule (such as glucose) from one side of the plasma membrane to the other. Receptors can bind an extracellular molecule (triangle), and this activates an intracellular process.
I think it's the 3rd one but im not sure
The properties that best measure the brightness of a star is it's Absolute magnitude from the standard distance of 32.6 light-years, or 10 parsecs.
<h3>What is star brightness?</h3>
According yo astronomers, star brightness is define base on the absolute magnitude of the star which is the degree in which the star is able to radiate or give more light .
It is define as the light intensity give out by stars.
Therefore, The properties that best measure the brightness of a star is it's Absolute magnitude from the standard distance of 32.6 light-years, or 10 parsecs.
Learn more about star brightness below.
brainly.com/question/14376690
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