Atoms may have different numbers of neutrons. Atoms are the smallest fraction of an element that can exist, and still show the properties of the element. They consists of electrons (negatively charged), protons (positively charged), and neutrons (no charge). The number of electrons is equivalent to the number of protons normally however an atom may loose or pick up electrons and have a positive charge or negative charge. The number of neutrons in the nucleus may vary within a given element to give varieties of atoms we call isotopes.
Answer:
chewing gum
Explanation:
when chewing gum you'll likely think back to the last time you had gum. The trick is to study while chewing gum and, when you chew another piece of gum, you'll remember back to when you had it earlier along with the information that you remembered as you were chewing the gum.
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>
Mesophiles are group of bacteria that grow best in such conditions.
Because it proves the fertilization was impossible
