Answer:
The purine ring is built onto ribose-5-phosphate of PRPP for its de-novo nucleotide biosynthesis, while the ring structure of the pyrimidine bases are synthesized separately and then coupled to ribose-5-phosphate via the C-N glycosidic bond.
Explanation:
In the de novo synthesis of nucleotides, their metabolic precursors such as aminoacids, ribose-5-phosphate, CO₂ and NH₃ are used as starting materials.
In purine nucleotide synthesis, the ring structure is built up on ribose-5-phosphate of PRPP by addition of one or a few atoms one at a time starting with the amino group donated by glutamine until the first intermediate inosinate is synthesized.
In pyrimidine ring synthesis, orotate is first synthesized from carbamoyl phosphate and aspartate, and then is attached to ribose-5-phosphate of PRPP, before it is then converted to the common pyrimidine nucleotides starting from uridylate.
The answer is D mitosis and cytokinesis
Answer:
A. It could increase the average water level of lakes in the area. ... It could cause a decrease in the amount of waste and pollutants in the water supply.
Explanation:
anthropology.................................
Yes. During meiosis Diploid (2n) mother cell produces fou haploid(n) daughter cell.
Explanation:
- Meiosis is also known as Reduction division.
- It is type of cell division by which a diploid mother cell produces haploid daughter cell.
- It is termed as reduction division because the number of chromosomes are reduced to half in daughter cell.
- Meiosis occurs only in sex cells to produce gametes.
- Significance of meiosis lie in the fact that it reduces the number of chromosome into half and thus helps to maintain the chromosomal number of the species in the zygote after fertilisation .
- Meiosis has two steps : Meiosis I and Meiosis II. There is a time gap between two steps, called interkinesis.
- Meiosis I involves replication , crossing over etc.
- Meiosis II is similar to mitosis however, no DNA replication occurs prior to meiosis II and the DNA content is thus halved in Daughter cell.
