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:
Posterior column mediates a pathway called as posterior column medial lemniscus pathway in central nervous which is responsible for mediating certain sensations like touch, vibration etc. Damage to the left posterior column unable to transmit signals to the primary somatosensory cortex in the gyrus and parietal lobe of the brain.
Explanation:
- The spinal cord and cerebrum is connected by some specialized tract called as white matter tract. These tracts are either ascending or descending.
- The another name of ascending pathway is known as medial lemniscus pathway.
- The origin of this pathway takes place within posterior column of the spinal cord.
- Posterior column medial lemniscus pathway is important as it transmit signals to the cerebrum which is responsible for generating impulse like vibration, touch etc.
- Thus damage to this column can't be able to transmit signals to different parts of cerebrum and thus impulse like touch, vibration,pressure etc will not generate.
Answer:
Fermentation
Explanation:
Fermentation is the process whereby carbohydrates are converted to acohol or acid by the activities of some enzymes. During the process of fermentation, carbon dioxide is produced and it is found as tiny pockets of air inside the bread dough. This make it to rise. The alcohol produced evaporates later during the bread making process.
Highly unlikely both parents have to be colorblind
