All mentioned complexes (receptor-hormone, antibody-antigen, enzyme-substate) are involved in a molecular recognition.The molecular recognition involves <span>non-covalent </span> interaction between molecules. To form complex, molecules must be complementary in shape and charges, and usually, they are compared to key and lock. This way, the selectivity and specificity of recognition between molecules are assured.
The answer is A. When a potent drug is discovered, it has to undergo animal and human trials to test it ADMET (Absorption, Distribution Metabolism, Excretion, and Toxicity) properties. Using tissue cultures to test drugs, such as cancer drugs, prevents the incidence of subjecting humans to the unknown adverse effects of the drugs before the drugs are determined to be safe for use.
Crowded between the collagen fibers are rows of fibroblasts, fiber-forming cells, that generate the fibers. Dense connective tissue<span> forms strong, rope-like structures such as tendons and ligaments.</span>
Answer with Explanation:
Gramicidine is an antibiotic that has a polypeptide structure and is composed of 3 chains. This molecule can adopt a structure called beta 6-3 helix, so as to form a channel through the cell membrane of bacteria which allows the passage of ions (in this case cations) such as H +, K + or Na +, this situation leads to that in the cell alterations in the content of cellular cations are generated, among the effects the loss of potassium that can cause the death of the cell due to hemolysis due to alteration in the permeability of the membrane is highlighted. This effect is known as the ionophore effect.
An ionophore effect leads to the inhibition in the release of H + to the mitochondrial electronic transport chain.
Gramicidin thanks to its mechanism of action, when it produces interference specifically in a cellular organelle called mitochondria in the inner mitochondrial membrane, it is responsible for interrupting the passage of electrons, alters the gradient of H + and the performance of the enzyme called ATP- synthase which is responsible for producing ATP.
The damage that the entire previous situation produces on oxidative phosphorylation, leads to the refusal of ADP refosphorylation, then ADP and its hydrolysis products will accumulate, and finally the result will be a decrease in ATP levels.
