Answer: Iron
Explanation:
hemoglobin: The iron-containing substance in RBCs that transports oxygen from the lungs to the rest of the body. It consists of a protein (globulin) and haem (a porphyrin ring with an atom of iron at its center).
Hope This Helps! :P
<span>Smooth Endoplasmic Reticulum consists of the Nuclear Envelope, the Rough Endoplasmic Reticulum, the Smooth Endoplasmic Reticulum, and areas that contact other organelles. The Smooth Endoplasmic Reticulum fold protein molecules I'm not that tired</span>
Answer: Invasive species can harm both the natural resources in an ecosystem as well as threaten human use of these resources. An invasive species can be introduced to a new area via the ballast water of oceangoing ships, intentional and accidental releases of aquaculture species, aquarium specimens or bait, and other means.
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.
