A gated channel is an example of facilitated diffusion. A gated channel protein is a transport protein that opens a "gate" allowing a molecule to pass through the membrane (usually molecules too big to enter the cell by passing through the membrane itself).<span> </span>Gated channels <span>have a binding site that is specific for a given molecule or ion. (meaning only certain molecules or ions can enter the channel).</span>
I don't even know the answer sorry
The ensemble of formations and folds in a single linear chain of amino acids sometimes called a polypeptide constitutes the tertiary structure of a protein. Finally, the quaternary structure of a protein refers to those macromolecules with multiple polypeptide chains or subunits.
The answer would be A—the molecular formula given is that of a long-chain, saturated fatty acid, which would be insoluble in water (i.e., hydrophobic).
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B describes carbohydrates, which can function as a storage of energy (e.g., starch or glycogen) or structural components (e.g., cellulose). The three examples just given are polymers of glucose, a monosaccharide; monosaccharide generally have the empirical formula CH2O; this is not the empirical formula of the given molecule (and, in any case, there are too few oxygen atoms for the number of carbon atoms), and so B is incorrect.
C describes an amino acid, likely an α-amino acid, which consist of a central, saturated carbon bonded to amino (—NH2) and carboxyl (—C(=O)OH) functional groups and a variable side chain, which determines the amino acid’s properties. Since the formula of an amino acid must contain nitrogen, which the formula given doesn’t have, the molecule couldn’t be an amino acid, and so C is incorrect.
D describes nucleic acids. Examples include DNA and RNA; nucleic acids and the nucleotide monomers that comprise them contain a nitrogenous base and a phosphate group. The given molecule’s formula has neither nitrogen nor phosphorus, and so cannot represent an amino acid, making D incorrect.
