The statement '(a) there are billions of galaxies in a galaxy cluster' accurately describes a relationship between two parts of the universe.
<h3>What is the solar system?</h3>
The solar system can be defined as a group of billions of galaxies that form a cluster due to gravitational forces that maintain all these celestial bodies linked together. This system contain our Sun.
In conclusion, the statement '(a) there are billions of galaxies in a galaxy cluster' accurately describes a relationship between two parts of the universe.
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I had to take a screenshot of my response since it was getting flagged for being inappropriate for some reason.
The right answer is the activation energy.
The catalyst increases the reaction rate by introducing new reaction paths (mechanism), and lowering its activation energy, or activation Gibbs free energy. By doing this it can increase the speed, or lower the temperature of the reaction. It is important to note that the catalyst does not alter the total Gibbs free energy of the reaction which is a system state function and therefore has no effect on the equilibrium constant.
The conduction of nerve impulses relies upon the movement of positively-charged ions across the nerve cell membrane. The entry of sodium into the cell produces a wave of positive charge that travels down the length of an axon. Then chemicals called neurotransmitters are secreted out of the end of the axon onto the next nerve in the series (the postsynpatic nerve). This narrow space in between neurons is called the synapse. These neurotransmiiters released by the presynaptic nerve bind to receptors on the postsynaptic nerve. The binding of these receptors opens up channels in this second nerve's membrane that allow sodium ions to enter the nerve cell and initiate another wave of positive charge, and so on... The nerve signal can only move as fast as these ions and neurotransmitters can diffuse to generate this process.
<span>As a professional athlete repeats a given activity many times over, the nerve cells "upregulate" their receptors, meaning that they produce additional receptors to put in the membrane. This is just a natural reaction to the nerve being repeatedly stimulated in the same way over and over. When neurotransmitter is secreted from the presynaptic neuron, there are more receptors on the postsynaptic neuron for it to bind, more channels open up, more ions enter in a shorter time and build up positive charge to create the impulse faster, and so the overall effect is faster. </span>
<span>Additionally, there are sheaths of fatty tissue (called myelin) that insulate the charge in the neuron and allow it to be conducted faster. As people age, these sheaths can start to degrade, making the nerve cell more "leaky" and causing the impulse to be conducted more slowly. </span>
HIV in fact kills the immune system cells causing our body cannot fight off infections and diseases from entering our body. this creates our immune system to become weaken.