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.
A i wrong because it says that they are similar.
B is wrong because archaea are phylogenetically similar to eukaryotes
C is also true because archaea are more phylogenetically similar to eukaryotes than bacteria
D is true because the Archaea did develop before Bacteria
so your answer is C because D says that archaea are different from bacteria because the archaea domain developed first, it does not say that they are dissimilar because of their appearance
Answer:
- gas
- liquid
Explanation:
Part of the definition of gases and liquids is the ability to flow, so this answers your question.
Why does this not apply to solids? The cells in a solid are closer together with less room for movement, so they do not "flow" like gasses or liquids. You can think of the device you are asking this question on versus the water in the ocean.
<u>Note</u>: Gas can still flow, but it does not flow the same as water. It depends on what you are being taught for if gas flows or not.
-> Liquid flows from high to low only, while gas can flow in all directions
Have a nice day!
I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)
★ Also please leave the rating you think I deserve (It helps other users as well as myself)
- Heather
Answer:
The Cardiovascular System
Explanation:
The respiratory system draws air into the lungs. Oxygen diffuses through the walls of the alveoli and across the walls of the capillaries where it enteres the bloodstream. The oxygen molecules are picked up by red blood cells, which are pumped through the blood vessels by the action of the heart. As the red blood cells carrying oxygen pass through capillaries near the cells, oxygen diffuses into the cells.
Answer:
the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a by-product.
