Answer:
When an action potential reaches the end of an axon, the nervous terminal or the varicosities release neurotransmitters. These bind to receptors on the postsynaptic neuron. Eventually, the neurotransmitters are removed from the synapse. Some are reabsorbed by the presynaptic neuron or sending neuron, a process called reuptake, and some are broken down, in a process called enzymatic degradation.
Explanation:
Neurotransmitter liberation occurs from the nervous terminal or varicosities, in the neuronal axon. There are vesicles in the sending neuron that have neurotransmitters in their interior. When an <em>action potential reaches the nervous terminal</em> or the varicosities, it occurs a notable increase in the <em>neurotransmitter liberation</em> by exocytose. This is possible because calcium channels open letting the ion in the cell through the membrane, and letting the neurotransmitter out to the synaptic space. The molecule binds to its receptor in the postsynaptic neuron. This receptor is a <em>protein structure that triggers an answer</em>. As long as the signal molecule is in the synaptic space, it keeps linking to its receptor and causing a postsynaptic answer. <em>To stop this process</em>, the <em>neurotransmitter must be taken out from the synaptic space.</em> There are two mechanisms by which the neurotransmitter can be eliminated:
Enzymatic degradation/deactivation: In the synaptic space, there are <em>specific enzymes that can inactivate the neurotransmitter </em><em>by breaking it down or degrading it</em><em>.</em> In this case, the new molecule won’t be able to bind to the neurotransmitter receptor.
Reuptake: There are receptors located in the presynaptic membrane that can capture de molecule to store it back in new vesicles, for posterior use. These <em>transporters are active transport proteins</em> that easily recognize the neurotransmitter.
Answer:
Bones produce blood cells. So, if there are no bones in our body, then our body cannot make blood. So the answer is B.
Answer:
D. Nucleic acids attach to the bases in the DNA.
Explanation:
Transcription begins when an enzyme called RNA polymerase is added to the DNA template and begins a new chain a new chain to produce complementary RNA. During the RNA synthesis transcription takes place, then the cap and tail is added and then splicing occurs. RNA polymerase moves from the 3 'end to the template strand creating the RNA-DNA double helix or similar the base sequences. This makes a chain with each sugar by the set of bonds called phosphodiaster linkage. Then, the enzyme unwind the DNA and begins the synthesis of RNA. Therefore, D. Nucleic acids attach to the bases in the DNA.
<span>A.let myself feel sad and then find ways to move on</span>
Mitosis never stops in most of the cells of our body like "Gastrointestinal tract", "that give rise to blood cells" etc.
But, it stops after the death of the body.
Hope this helps!