Protein
<span>Cell membranes contain membrane proteins that allows all the interaction that occurs within the cell. It makes the cell membrane selectively permeable because of its characteristics as being fluid or its fluidity which means to say that they can move freely within the lipid bilayer. The membrane proteins can also be stored in the lipid bilayer together with the enzymes. It cannot be denied that membrane proteins have a lot of functions based on its type. They can be integral proteins, peripheral proteins and lipid bound proteins.</span>
4 is the answer; the cytotoxic t cell ain't with the bs.
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Had to look for the options and here is my answer:
Drosophila is considered as a specie of flies, often known as "fruit flies". In their development, the influence of the bicoid protein differs along the axis of the embryo because of the presence of <span>an anterior to the posterior gradient in BICOID protein concentration in the embryo. Hope this helps.</span>
We can say that the water is the solvent, and the powder is the solute. This is also a solution altogether.
<span>Explanation:- A solute is the thing being dissolved into the solvent. While the solvent is what when the solute is being dissolved in. Together, they make a solution. </span>