Activation of muscle contraction could be a speedy event that's initiated by electrical activity within the surface membrane and transversal (T) tubules. This can be followed by unharness of metal<span> from the inner membrane system, the sarcoplasmic reticulum.
</span>Nervous stimulation causes a depolarization<span> of the muscle membrane (sarcolemma) </span>that<span> triggers </span>the discharge<span> of </span>calcium<span> ions from the sarcoplasmic reticulum.</span>
... termed "hypotonic," meaning less solids (or more diluted) than inside the cell. For fluid movement in/out of cells, water will diffuse (via osmosis) from the hypotonic solution to the hypertonic one, assuming a permeable barrier (i.e. cell membrane) allows it. With this case, water will flow into the cell from outside.
Brain energy requirement, metabolism and neurotransmitter turnover consume 20 % of the available oxygen and glucose in the body.
<span>Even though, the brain is only about 2% of the body weight, it consumes about 20% of the body's energy. It is the main consumer of glucose-derived energy. When the mental strain increases, the brain's demand for energy in the form of oxygen and glucose is higher.</span>
Answer:
__ It implies that prokaryotes existed before eukaryotes, and
__ It implies that eukaryotes evolved from prokaryotes.
Explanation:
The prefix pro- can mean "before". By using the term prokaryote one can tend to think that procaryotes preceded eukaryotes.
Preceed as existed before them, or as an evolutionary point of view.
