Answer:
150 individuals
Explanation:
If the dark phenotype is determined by a dominant allele at a single locus, the ratio of dark green phenotype to pale green phenotype at F2 should be 3:1 according to the Mendelian standard.
200 to 3:1 = 150:50
<u>Hence, if 200 F2 individuals were characterized, one would expect the number of dark green individuals to be 150 while the pale green would be expected to be 50.</u>
Answer:
The tabby cat has inherited color traits from both parents and shows amixture of both colors
Explanation:
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.