at what stage of human development wuold you exept to first see abeating heart? <u>the</u><u> </u><u>answ</u><u>er</u><u> is</u><u> </u><u>ç</u>
Answer:
False
Explanation:
The histones that are more positively charged, tight hardly to negatively charged DNA. So, enzymes, such as acetyltransferases, that reduce the positive charge of histones promote transcription.
Chromatin structure and its modifications can change the package of the DNA and consequently, alter the gene expression. The most common modifications of the chromatin are covalent modifications such as acetylation/deacetylation (by acetyltransferases and eacetylases), methylation (by methyltransferases), and phosphorylation (by kinases). This is the way of gene expression regulation.
The effects of modifications are different, for example methylation promotes condensation of the chromatin and as a consequence, prevents binding of transcription factors to the DNA (transcription is repressed).
Acetylation loosens the association between nucleosomes and DNA (because it neutralizes the positive charge of histones) and consequently promotes transcription. Deacetylation is a process opposite to acetylation.
Answer:
Brassica species are dicot which means that they have two cotyledons instead of one like monocots. Cotyledons supply food for the plants in the seed. As the plant matures, it flowers. Mustard plants have small yellow flowers in clusters.
Answer:
D. anything in the atmosphere.
Explanation:
<span>Tetraphenylcyclopentadienone has five conjugated aromatic rings. Its structure suggests that it is highly conjugated. With this structure, it absorbs the energy from wavelengths of colors other than violet and reflects the energy from violet wavelengths.</span>