Answer:
Scientists began to mark division on the geologic time scale when patterns and similarities started emerging from archeological studies. Patterns such as the discovery of fossils that were formed within the same period.
Explanation:
Geologists who study matter that make up the Earth's crust (whether solid gaseous or liquid), as well as matter from other terrestrial planets and the processes that influence the formation and condition of this matter, are called geologists.
They have successfully calibrated history into various phases of time intervals. These intervals are event-based intervals. For example, you have Eons, Eras, and Periods.
An Eon is a billion years. An example is the Neoproterozoid Eon. Eons are made up of several Eras and Eras are made up of periods. An example of an era is the Mesozoic era. Whilst periods are smaller units of an era, eg. Triassic era.
As scientists deduced the causes for the formation of fossils and topographical remains/patterns, they collected events that occurred within the same time period and group them together.
This range of events became known as the geological time scale.
The age of fossils and rocks is also used to map out the calibrations on the scale.
The age of fossils and rocks is determined using the process of radioactive dating.
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<span>There are many interesting aspects in these statues of the sphinx which is basically a limestone statue of lion with man's head. So this particular headdress of rearing cobra which was worn on the head of the Sphinx is that it is believed of giving protection from the evil forces.</span>
No Because There Are A Lot Of Different Elements That Make Up Just One Cell And You Have Millions Of Them That Make Up You And Different Ones For Different Functions In Your Body. So I Wouldn't Call Them Simple At All
Answer:
1. d. changes in the methylation patterns of <em>loci</em> involved in growth and metabolic disease
2. b. differences in the expression of metabolic genes
d. changes in histone acetylation patterns
Explanation:
Epigenetics refers to the study of heritable changes in gene expression which are not dependent on DNA sequence. Epigenetic mechanisms involve DNA methylation, histone modifications (acetylation, methylation, phosphorylation, etc) and regulatory non-coding RNA (ncRNA) pathways. These epigenetic mechanisms work together and mutually reinforce each other in order to modulate gene expression (either by activating or suppressing gene expression). In consequence, transcriptome data (e.g., genes differentially expressed in particular tissues/cells or stages of development) is an important piece of evidence indicating the existence of epigenetic modulation.
