Hadean is the first eon of precambrian, and took place around 4.6 and 4.0 billion years ago.
DNA is condensed by a certain amount just on its own, just by its own interactions within the DNA molecule,..but whne proteins get involved it gets condensed 30000 fold
<span>what happens is that proteins called histones are like hockey pucks, and DNA wraps around it 1.5 times and then goes to another histone and wraps around that so that it looks like beads on a string (i hope that makes sense, its the only way to describe it) </span>
<span>these histones condense this DNA a lot, and when the histones get methylated then the DNA packs together even closer to get heterochromatin (VERY densely packed DNA)...the theory here is that DNA has a net negative charge due to the phosphate groups in the DNA backbone and doesnt allow the DNA to come together as closely as it could (like charges repel like charges), but when histones are methylated, the negative charge on the DNA is masked by the methyl groups and DNA can come together closer </span>
Answer:
B. stomata.
Explanation:
Stomata are openings in the surface of the plant epidermis through which gases and water vapor pass. They are formed by two elongated cells whose shape is similar to bean grain or dumbbell depending on the species. These cells are called guard cells, and in their midst there is a slit called the ostiole.
The stomata make the exchanges between the external and internal environment of the plant. They regulate the size of the opening, so it is possible to increase or decrease the rate of perspiration of the plant.
Stomata are usually located at the bottom of the leaf, but in aquatic plants such as the water lily they are at the top and still in vertical growing plants on both sides.
Answer:
Explanation:
It takes 27.3 days for moon to make one revolution this is called sidereal month and it takes 29.5 days to complete a cycle of phase this is called synodic month. The synodic month is difference is because as the moon moves around earth, the earth is also moving round the sun. Hence, the moons needs to move farther away to make up the distance that was added as the earth also revolves in other to complete the cycle.