Answer: The removal of rock particles by wind, water, ice, or gravity. Works with weathering to continuously wear down and carry away rocks at Earth's surface.
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.
It would be uracil (C)
thymine would be complementary to adenine in DNA but because it is RNA it is replaced by uracil.
Answer:
Humoral immunity involves <u>B cells</u> and<u> recognize antigens or pathogens in the lymph or blood.</u>
Explanation:
Humoral immunity is defined as the immunity which is mediated by several macromolecules presnet in the extracellular fluids such as antibodies, certain antimicrobial peptides, and complement proteins.
Humoral immunity allows to distinguishes two groups of foreign substances. it involves <u>B cells</u> and<u> recognize antigens or pathogens in the lymph or blood. </u>
Humoral immunity begins when an antigens bind to B cells. Interleukins or helper T cells provides a secondary signal to the B cells that activates a B cell and allows B cell proliferation. which roduces produce plasma cells. The plasma cell then produces antibodies which are identical to the specific antigen. The antibodies are the released and circulate through the body, binding to antigens. B cells the further produces memory cellss for future immunity.
So, Humoral immunity involves <u>B cells</u> and<u> recognize antigens or pathogens in the lymph or blood.</u>
Answer:
all of the above
Explanation:
gravity makes a planet have a combination go straight yet go around the sun at the same time creating an ellipse
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