The question is incomplete as it does not have the options which have been provided in the attached file.
Explanation:
1. Dura mater: the dura mater is the most superficial layer which is characterized by the folds. The dura mater forms the walls between the hemisphere of the brain that is between right and left halves of the cerebellum. The structure present in the dura mater is tentorium cerebelli and super sagittal sinus.
2. Pia mater: the deepest layer present which is adhered to the tissues of the brain. The cortical gyri blood vesicle are superficial to the pia mater.
3. Arachnoid mater: the middle layer which is characterised by transparent and gelatin-like appearance.
Cellular products such as hormones and neurotransmitters are released by the process of exocytosis. <span> Exocytosis is the term that describes the transport of material out of a cell.</span>During this process <span>vesicles fuse with the plasma membrane and release their contents to the outside of the cell.
</span><span>This process is the counterpart of endocytosis.</span>
Answer: b. reaction 3
Explanation: When an enzyme is present in a reaction acts as a catalyst, increasing velocity of reaction and decreasing the activation energy, when not present an enzyme the reaction velocity is very low and implies high activation energy, being unfavorable to the system