Answer:
In the absence of sunlight the plants which are dependent on sunlight for making food that is photosynthesis would die.
Also the people will suffer as sunlight is a good source of Vitamin D and in absence of sunlight they will not get it so easily.
Answer:
I believe that the answer would be 39 and 78
Microorganisms that are involved in the nitrogen cycle are able to break the triple of elemental nitrogen using special enzymes that they have developed and make ammonium. Other organisms like plants are unable to break the triple bond and therefore rely on these microorganisms so that they can absorb the ammonia
In the case of chronic bronchitis or chronic inflammation of the airways, cyanosis or the bluish discoloration of the skin results from the reduced levels of oxygen in the blood. With reduced oxygen levels, the blood in the arteries will not be bright red in color but rather be brownish just like venous blood and this reflects in the skin as bluish in color.
Answer:
A) Times of major climate change
Explanation:
The geological time scale is based on major changes in Earth's climate history. This is because of the reason that climate governs the geological processes on Earth. In geology, we study the ages with the help of stratigraphical data where sediment deposition and the fossils it is hosting are the keys to understand the environmental conditions at that particular time. These conditions didn't change significantly unless the climate was changed. An example is the extinction of dinosaurs during K/T boundary event (mass extinction). The most likely reason is the hitting of a meteorite on Earth that changed the climate of Earth in a short period making it least favorable for many organisms to survive.
On the other hand, the occurrence of huge events cannot be used to establish a geological time scale because sometimes, the changes happen more slowly.
Similarly, shifts in the Earth orbits are cyclic however geological time scale doesn't reflect cyclic changes. The same climate can establish in different ages but these events are not used not as a criterion to establish a geological time scale.
In the end, the time span of humans on Earth is very small when compared with the overall geological time scale. Humans record exists from Pleistocene (2,580,000 to 11,700 years ago) to today whereas geological time scale starts in the Archean Eon (4.0 billion to 2.5 billion years ago).
