Correct answer: D) From bacteria living in their roots
Nitrogen is an essential plant nutrients, but it is metabolically unavailable to higher plants and animals. It is available to some species of microorganism by biological nitrogen fixation in which nitrogen is converted to ammonia with the help of enzyme dinitrogenase.
The process of breaking apart the two atoms in a nitrogen molecule is called nitrogen fixation. Plant obtain the nitrogen they need from the soil which is already fixed by the bacteria and archae.
Example: <em>Azobacter</em><em>,</em> Nostac
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.
Yes accumulation of mutation can drive aging process.
Explanation:
The molecular damage that occurs in cells and tissues for a long time due to DNA damage and epigenetic changes gets accumulated in the cell.
This leads to lowering of the homeostasis in the cell during stress conditions and eventually risks of life-threatening diseases as cancers or neurodegenerative disorders develop.
Due to mutation in the gene DNA repair mechanism also gets affected this also contributes to the ageing of cells.
The telomere of the chromosome is shortened after every mitotic division but telomerase enzyme keeps adding the DNA sequence preventing shortening aging and death of the cell. If the mutation occurs in this enzyme it will increase the ageing of cells at high rate.
Answer:
b
Explanation:
you just have to think about the definition of unity. the word unity comes from unite. unite many pieces and you get a whole.
