<h2>Energy </h2>
Explanation:
Energy flows in only one direction through an ecosystem
- The Sun supports most of Earth's ecosystems
- Plants create chemical energy from abiotic factors that include solar energy and chemosynthesizing bacteria create usable chemical energy from unusable chemical energy
- The food energy created by producers is passed to consumers, scavengers, and decomposers
- Energy flows through an ecosystem in only one direction, it is passed from organisms at one trophic level or energy level to organisms in the next trophic level
- Most of the energy at a trophic level – about 90% – is used at that trophic level and organisms need it for growth, locomotion, heating themselves, and reproduction
- So animals at the second trophic level have only about 10% as much energy available to them as do organisms at the first trophic level
- Animals at the third level have only 10% as much available to them as those at the second level
The "Spanish" influenza pandemic of 1918–1919, which caused ≈50 million deaths worldwide, remains an ominous warning to public health. Many questions about its origins, its unusual epidemiologic features, and the basis of its pathogenicity remain unanswered. The public health implications of the pandemic therefore remain in doubt even as we now grapple with the feared emergence of a pandemic caused by H5N1 or other virus. However, new information about the 1918 virus is emerging, for example, sequencing of the entire genome from archival autopsy tissues. But, the viral genome alone is unlikely to provide answers to some critical questions. Understanding the 1918 pandemic and its implications for future pandemics requires careful experimentation and in-depth historical analysis.
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.
Explanation:
However, in 2016 researchers published a new set of Neanderthal DNA sequences from Altai Cave in Siberia, as well as from Spain and Croatia, that show evidence of human-Neanderthal interbreeding as far back as 100,000 years ago farther back than many previous estimates of humans' migration out of Africa (Kuhlwilm Dec 11, 2020
