Answer:
Diffusion describes the movement of particles from an area of higher to lower concentration. That is what the ink is doing when it spreads throughout the jelly. Osmosis only occurs across a semipermeable membrane.
The correct answers are:
- Methylation of histone tails in chromatin can promote condensation of the chromatin.
- DNA is not transcribed when chromatin is packaged tightly in a condensed form.
- Acetylation of histone tails is a reversible process.
- Some forms of chromatin modification can be passed on to future generations of cells.
- Acetylation of histone tails in chromatin allows access to DNA for transcription.
Histone modifications are post-translational modifications of histone protein that can affect gene expression by altering chromatin structure or recruiting histone modifiers.The most common modifications are methylation, phosphorylation, acetylation and ubiquitylation. All of them affect the binding affinity between histones and DNA and thus loosening (gene activation) or tightening (gene repression) the condensed DNA.
Histone methylation is a transfer of methyl group by histone methyltransferases to lysine or arginine amino acid of protein. Effect of methylation depends on the type of protein that is modified. Demethylation is the reverse process.
Histone acetylation is the process of adding of an acetyl group(by histone acetyltransferases) to histone proteins and it can also activate or inhibit the gene expression. Deacetilation is reverse process.
Answer:
The answer is A. Light is converted into ATP.
The modern theory of evolution is easiest illustrated by the tree of life. This is a metaphoric visual representation off all past and present species (as far as we know them).
The root or origin of the tree represents the origin of life on earth. This is still a debated subject, but for the tree of life, it is assumed that it was a single celld organism.
This single cell, over time, evolved into the species that now live on Earth. Each species has its place on the tree's branches, which illustrate the evolutionary relationships and evolution on all life on earth. The closer the species are on the branches, the closer related they are.
Thus, according to the theory of evolution, at some point in time a fruit fly and a fruit bat <em>did share a common ancestor</em>. However, due to the fact that fruit flies are insects and bats mammals, they are part of different phylum (insects - Euarthropoda and mammals - Chordata).
Both species are far apart on the tree of life and which makes their common ancestor to have existed a long, long time ago, well over 525 million years (when the first vertebrates evolved).