Stellar evolution is the process by which a star undergoes a sequence of radical changes during its lifetime. Depending on the mass of the star, this lifetime ranges from only a few million years (for the most massive) to trillions of years (for the less massive), considerably more than the age of the universe. ^
Small, relatively cold, low mass red dwarfs burn hydrogen slowly and will burn for hundreds of billions of years
Massive hot supergiants will live for just a few million years.
A mid-sized star like the Sun will remain on the main sequence for about 10 billion years. Hope tis helps!!
Answer: it is difficult because it is necessary to understand some concepts used in a system. For example what is a boundary, and environment which can be positive or negative, etc. A sample could be the course OpenLearn that provides an example of Computing & IT.
Explanation:
Answer:
Bioluminescence is the phenomenon which is seen in the dinoflagellates which is very common. It is caused due to chemical reactions that takes place inside the organism.
There is an influx of protons in the cell which drops the pH of the cell. It is the oxidation of luciferin which produces the glow.
This phenomenon acts as a shock for the predator because it is in the form of flash for less than 20 microseconds.This flash reduces the number of dinoflagellates which is being eaten by the predator.
Anaerobically (in absence of oxygen), yeast cells may obtain energy by fermentation, resulting in the production of ATP, CO2 AND ETHANOL. This is called ethanol fermentation or alcoholic fermentation where sugars such as glucose, fructose, and sucrose is converted into cellular energy (ATP), producing ethanol and carbon dioxide as by products.
