The hydrogen bonding of nucleotides into a new DNA molecule is facilitated by enzymes. Hydrogen bonding is the electromagnetic attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. The nucleotides in a base pair are complementary which means their shape allows them to bond together with hydrogen bonds. The A-T pairs forms two hydrogen bonds while the C-G pair forms three. The enzymes called DNA polymerases join the nucleotides by way of phosphodiester bonds.
It would be difficult to find the ideal CO2 level with a low light intensity because the plant will have a difficult time trying to survive.
Answer:
Mangrove forest
Explanation:
Mangrove forest exist only in high saline environment. Lake is a closed type body of water so it is expected with the least variation of salinity.
Answer:
Some forms of chromatin modification can be passed on to future generation of cells
Acetylation of histone tails in chromatin allows access to DNA for transcription
DNA is not transcribed when packaged tightly in a condensed form
methylation of histone tails can promote condensation of the chromatin
Explanation:
chromatin modifications that can be passed on includes epigenetic modifications that are heritable changes made to the chromatin structure that does not involve the DNA sequences. Some epigenetic modifications include DNA methylation and Histone modifications. examples of histone modification include acetylation, methylation, phosphorylation, ubiquintylation etc. All these function either in allowing the DNA become more accessible to transcritional factors or vice versa. for exmple, histone tail acetylation encourages unwounding of nucleosomes allowing transcriptional factors to have access to the DNa while histone tails methylation further tightens the nucleosomes promoting condensation of the chromatin.
Answer:
Upon nutrient limitation, budding yeast will produce daughter cells less than 20% of the mother cell size. This asymmetric division may select for growth functions that are efficient over a larger range in cell sizes, such as exponential growth. In turn, efficient growth over a large size range lessens the pressure to have precise size control.
Explanation:
In wild-type cells growing in nitrogen-rich medium, the size threshold to enter mitosis is high, and the G1/S size control is cryptic because cell division produces daughter cells with a size greater than the minimum required to initiate S phase. In these conditions, G2 is long and G1 is short. However, the cell size threshold to enter mitosis is greatly reduced when wild-type cells are shifted to medium with a poor nitrogen source, such as minimal medium with proline, isoleucine, or phenylalanine. In these conditions, wild-type cells initiate mitosis at a reduced cell size, generating two daughter cells that are smaller than the critical size threshold required to progress through G1/S
