Explanation:
Almost all eukaryotic proteins are subject to post-translational modifications during mitosis and cell cycle, and in particular, reversible phosphorylation being a key event. The recent use of high-throughput experimental analyses has revealed that more than 70% of all eukaryotic proteins are regulated by phosphorylation; however, the mechanism of dephosphorylation, counteracting phosphorylation, is relatively unknown. Recent discoveries have shown that many of the protein phosphatases are involved in the temporal and spatial control of mitotic events, such as mitotic entry, mitotic spindle assembly, chromosome architecture changes and cohesion, and mitotic exit. This implies that certain phosphatases are tightly regulated for timely dephosphorylation of key mitotic phosphoproteins and are essential for the control of various mitotic processes. This review describes the physiological and pathological roles of mitotic phosphatases, as well as the versatile role of various protein phosphatases in several mitotic events.
Answer:
Primary succession is the orderly and predictable series of events through which a stable ecosystem forms in a previously uninhabited region. Primary succession occurs in regions characterized by the absence of soil and living organisms.
Answer:
Option (3)
Explanation:
The continental crust is usually thick because it has an average thickness of about 35-40 km. In the high mountain ranges, it is the thickest, forming about 80 km on an average. These are formed when two continental plates form a sandwich pattern by sharing a convergent type of plate boundary.
For example, the thickest part of the crust is the Mt. Everest which lies in the great Himalayan range, which has started to form about 50 million years back. It is geologically the most recent mountain range.
The older mountains are continuously eroded in the geological past, as a result of which the height of the mountains is affected.
Thus, the correct answer is option (3).
Answer:
D is the correct option
Explanation:
expansion of water is not significant over day night temperature
Answer:
It seems that a reciprocal translocation is going on.
Explanation:
A translocation occurs when a chromosomal fragment changes its location in the same chromosome from the original to a new one. Or when it leaves the chromosome to re-locate in a new different chromosome.
According to this, there are different types of translocations:
- Intrachromosomal translocations:
- Intra-radial: the change in position occurs in the same arm of the chromosome. For instance, 123.456789 → 123.478569
- Extra-radial: The change in position occurs from one arm to the other of the same chromosome. For instance, 123.456789 → 15623.4789
- Extrachromosomal translocations:
- Transposition: not reciprocal interchange. The fragment leaves a chromosome to re-locate in another chromosome. The other chromosome does not send any fragment to the first one.
- Reciprocal translocation: There is a reciprocal interchange. A fragment of chromosome A goes to B, and a fragment of chromosome B goes to A.
Reciprocal translocations might be:
- Fraternal: the interchange occurs among homologous chromosomes
- External: the interchange occurs among non-homologous chromosomes
Reciprocal translocations are easily recognized during meiosis because an association between four chromosomes can be observed. This association is a quadrivalent structure.
During metaphase 1, the centromeres involved in the quadrivalent originate centromeric co-orientation or disjunction.
