Cyclins
are the chemicals that regulate the cell cycle. Cyclins work by regulating the timing
of the cell cycle in eukaryotic cell. Cyclins activates cyclin dependent
kinases (CDKs) (an enzyme that works by adding <span>negatively charged phosphate groups to other
molecules in a process called phosphorylation) by binding to it to form a cyclin-Cdk
complex. This complex then functions by acting as a signal to the cell to move
to the next cell cycle phase. At the end of the event, the cyclin is degraded, Cdk
is deactivated, therefore signaling exit from a specific phase.</span>
Answer:
Explanation:
By using the radioactive dating to compare the ages of the rocks in different layers is the best way to compare the ages of layers from the two different areas as there is a sect in a rock formation, the oldest rocks are in the bottom layer and the most newborn rocks are in the top layer. Geologists have produced a set of principles to compare the ages of rock layers. They apply these principles to organize the layers according to their corresponding ages.
The eons that make up 90% of Earth's history are the Precambrian eons, which consists of Hadean, Archean, and Proterozoic eons.
Answer:
The answer is » Both processes produce carbon dioxide.
The answer is that the equatorial regions receive sun rays closest to the vertical (direct rays) because of their position relative to the equator where the tilting of the earth only mildly affects the climate. The climate along the equator changes very little through out the year and has summer like conditions for most of the year.
However the other regions may receive direct sun rays but for far more limited periods. In the months of July and August (summer months), the northern hemisphere is tilted towards the sun and receives the most direct rays. The opposite occurs in December and January when it is tilted away from the sun and thus winter sets in, whereas the southern hemisphere is at this time tilted toward the sun and receives the most direct sun rays.
