Answer:
In eukaryotes, it is well known that polyadenylation is required to produce the mature messenger RNA (mRNA) molecule and it provides stability to the mRNA during translation initiation. In prokaryotic organisms, polyadenylation is required for the degradation of the mRNA in a mechanism that involves three steps: endonucleolytic cleavage, polyadenylation and exonucleolytic degradation. Moreover, it is also important to note that no evidence of polyadenylation has bee reported in some prokaryotes including the halophilic bacteria Haloferax volcanic (Slomovic et al. 2005).
Citation:
Slomovic, S., Laufer, D., Geiger, D., & Schuster, G. (2005). Polyadenylation and degradation of human mitochondrial RNA: the prokaryotic past leaves its mark. Molecular and cellular biology, 25(15), 6427-6435.
Yes, protists have cell walls.
Protists cell walls are made of composed cellulose, protein strips , and silica
For some protists, we can even found components like pectin on the cell walls
hope this helps
Answer:
Monospermy and Physiological Polyspermy. In general, the entry of more than two spermatozoa into the egg cytoplasm, referred to as polyspermy, causes aberrant effects on meiosis completion or embryo development and hence embryonic death, due mainly to excess male centrosomes delivered into the egg.
Explanation:
Answer:
cytoskeleton
Explanation:
cytoskeleton is a microscopic network of protein filaments and tubules in the cytoplasm of many living cells, giving them shape and coherence.
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.
