Answer:
The correct answer will be option-B.
Explanation:
Viral polymerases are the enzymes which play an important role in the viral genome transcription and replication.
Retrovirus is the single-stranded RNA viruses which replicate through a DNA intermediate and therefore requires the <em>RNA-dependent DNA polymerase or reverse transcriptase</em>. Reverse transcriptase encodes DNA from the strand of RNA which can be replicated and helps in the reproduction of the virus.
Thus, option- B is the correct answer.
Answer:
For regulating activities of cell.
Explanation:
Ad nucleus consists of genetic materials like DNA,RNA which is responsible for controlling and directing all the activities of cell.
D, this competition effects death rates, birth rates hence effecting growth rates, in A less dense area competition would be low increasing birth rates and growth rates while decreasing death
Answer:
a) DNA fragments associated with histone proteins are all multiple in length (i.e., 260 bp, 520 bp, 780 bp, etc), thereby suggesting the presence of a pattern of organization in the chromatin
b) it suggests that each unit of organization (ie, each nucleosome) consists of 260 bp associated with chromatin proteins
Explanation:
The nucleosome is considered as the basic unit of chromatin. A nucleosome consists of approximately two turns of DNA wrapped around a core of eight histone proteins (i.e., a histone octamer). The histone octamer consists of two copies of each of the histones H2A, H2B, H3, and H4. Moreover, the nucleosomes are connected together by linker DNA sequences which vary between 10 and 100 bp in length.
Interphase: Chromosomes duplicate, and the copies remain attached to each other.
Prophase: In the nucleus, chromosomes condense and become visible. Spindle fibers begin to form.
Prometaphase: The nulcear membrane breaks apart, and the spindle starts to interact with the chromosomes.
Metaphase: The copied chromosomes align in the middle of the spindle.
Anaphase: Chromosomes separate into two genetically identical groups and move to opposite ends of the spindle.
Telophase: Nuclear membranes form around each of the two sets of chromosomes, they begin to spread out, and the spindle begins to break down.
Cytokinesis: The two cells split into two daughter cells, each with the same number of chromosomes as the parent cell.
