Answer: Extracellular [Ca2+]
Explanation:
The sensitivity and density of the alpha receptors serve to <em>enhance the response to the release of</em> <em>norepinephrine (NE)</em> . However, they do not exert a strong influence as the concentration of calcium ions on the amount of <em>norepinephrine (NE)</em> released by sympathic nerve terminals.
The release of neurotransmitters depends more on either an external or internal stimulus.This results in an action potential which on reaching a nerve terminal, results in the opening of Ca²⁺ channels in the neuronal membrane. Because the extracellular concentration of Ca²⁺ is greater than the intracellular Ca²⁺ concentration, Ca²⁺ flows into the nerve terminal. This triggers a series of events that cause the vesicles containing <em>norepinephrine (NE)</em> to fuse with the plasma membrane and release <em>norepinephrine (NE)</em> into the synapse. The higher the action potential, the higher the Ca²⁺ flow into the terminals resulting in higher amount of <em>norepinephrine (NE)</em> into the synapse, and vice versa.
Catechol-O-methyltransferase (COMT) is one of several enzymes that degrade catecholamines such as dopamine, epinephrine, and norepinephrine. It serves a regulatory purpose to lower the concentration of norepinephrine upon its release from nerve terminals.
Answer:
None of the conditions will favor either the forward reaction or backward reaction , hence the answer is D
Explanation:
- The principle of chemical Equilibrium is applied here, where the concentration of the reactants or the forward reaction is same as the concentration of the products or the backward reaction.
- The equilibrium constants is also involved here, K can be in terms of pressure (Kp) or concentration (Kc) hence equilibrium constant is the ration of the concentration of the products to the concentration of the reactants raised to the power of the coefficient of the reactants and products.
- Partial pressure , total pressure and the mole fraction relationship is also applied
- The step by step explanation is as shown in the attachment below.
Enzymes affect the rate of the reaction in both the forward and reverse directions; the reaction proceeds faster because less energy is required for molecules to react when they collide. Thus, the rate constant (k) increases. Figure 3: Lowering the Activation Energy of a Reaction by a Catalyst.
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Unpaired electrons are those electrons which exist singly in orbital, without making pair with other electron
CALCIUM:
Atomic Number 20
Electronic Configuration; 1s², 2s², 2p⁶, 3s², 3p⁶, 4s²
Number of Unpaired e⁻s; Zero
ARGON:
Atomic Number 18
Electronic Configuration; 1s², 2s², 2p⁶, 3s², 3p⁶
Number of Unpaired e⁻s; Zero
ALUMINIUM:
Atomic Number 13
Electronic Configuration; 1s², 2s², 2p⁶, 3s², 3p¹ (Ground State)
Electronic Configuration; 1s², 2s², 2p⁶, 3s¹, 3px¹, 3py¹ (Excited State)
Number of Unpaired e⁻s; 1 in Ground state and 3 in Excited State.
CARBON:
Atomic Number 6
Electronic Configuration; 1s², 2s², 2px¹, 2py¹ (Ground State)
Electronic Configuration; 1s², 2s¹, 2px¹, 2py¹, 2pz¹ (Excited State)
Number of Unpaired e⁻s; 2 in Ground state and 4 in Excited State