Ecological succession is the process of change in the species structure of an ecological community over time. The time scale can be decades, or even millions of years after a mass extinction
Metabolizing nitrogen in prokaryotes is very important to other organisms since these prokaryotes are able to convert ammonium in the soil to nitrate and, then, the denitrifying bacteria could use the nitrate produced instead of using oxygen in their metabolism in order to release nitrogen molecules. by the denitrification process, thus completing the nitrogen cycle. Without the nitrogen metabolism in prokaryotes, the nitrogen in the atmosphere could not be used or utilized to synthesize essential organic compounds that are needed by other organisms. It is only the prokaryotes that has the ability fixing nitrogen or can do the process of nitrogen fixation.
The gene which is produced once or twice in a lifetime is the milk producing hormone after childbirth. This is because it is produced only after the birth of the child. The growth of the mammary glands takes place during pregnancy. The breast continue to increase in size after giving birth to a child. After delivery only copious milk is produced which is generally done with the help of milk hormone. During pregnancy the secretion of the milk is inhibited by the estrogen and progesterone which circulates in the blood stream which in turn inhibits the release of prolactin from the pituitary gland thus making the mammary glands unresponsive. Where as insulin is a hormone which helps the body to utilise the sugar or glucose from different sources like carbohydrates that we get while we eat food and adrenaline is secreted when we are scared or when we feel that we are in danger. Therefore, milk producing hormone is the gene that are turned once or twice in a lifetime.
They are called
a. sunspots
The answer is 4. Mitochondria
