Answer:d. allow water to cross the plasma membrane via facilitated diffusion
Explanation:yeah
Active transport is a cellular transport mechanism. It’s the movement of molecules that are assisted by enzymes along the way to a higher concentration.
In the military strategy of the south the army remains effective, and mobile before an enemy that is stronger to wear it off over time. The plan of the military strategy of the north has three steps: the Union called for the blockade of the south coast, the capture of Richmond, the capture of Mississippi R. With this plan they toppled the south.
The antigen-binding sites of an antibody molecule are formed from the molecule's variable regions which are described as so because their amino acid sequences can be different on different antibodies.
The specificity of antibodies is determined by the variable regions found at their endpoints. Antibodies are specialized proteins secreted by B-cells of the immune system. They are also called immunoglobulins. They contain four polypeptide chains that comprise two heavy chains and two light chains to form a Y-shaped molecule.
The variable regions, more specifically the hypervariable regions of an antibody, have a high ratio of different amino acids with the most common amino acids provided in one place. The variable region serves as the antigen-binding site while the constant region found below the variable region is determined to invade the antigen.
Antibodies are preserved in our body to identify the antigen the next time it encounters. They send the signals to the other body parts to reject the antigen and invade it.
To know more about variable regions of antibodies, refer to the following link:
brainly.com/question/17439586
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Because acids have a bitter taste i believe
