Answer:
Mutations leading to the better attachement of virus to the host cell would allow the virus to spread the infection and leave more progeny. The reproductive fitness of mutant viruses would allow the mutation to spread.
Explanation:
1. The organisms with same resource requirement compete with each other. Viruses are not living things but once inside the host cell, they behave like living things. Rapid multiplication of virus overpopulate the host cells.
2. Genetic variations are added to the viral progeny by random errors during replication of the viral genome. These random variations may impart beneficial trait, harmful feature or remain neutral. If a random mutation in the SARS-CoV2 virus allows it to adhere better to the cells of the respiratory system, the virus would be better able to infect these cells to spread the infection. Once inside the host cells, the mutant virus would leave more progeny. On the other hand, the wild type virus that lack this mutation would have lesser chances of entering the host cells and may or may not replicate.
3. The progeny of the mutant virus would compete better with the non mutant ones due to the presence of same mutation.
4. Differential reproduction and more progeny of the mutant virus would spread the mutation among the virus.
Answer:
The accessory pigments like carotene & xanthophyll necessary to have in green plants is chlorophyll
Explanation:
Various pigments present in the plants helps in the absorption of the light, at photosynthesis. They acts as helpers to the plants. Chlorophyll helps in the green plants for absorption of light through which they can prepare their own food. The electrons in the molecular level of chemical structure of the pigment moves at certain energy levels. The chlorophyll is again divided into different types i.e. chlorophyll a,b,c,d. In case of plants chlorophyll a and chlorophyll b are the most important.
The Photosynthesis process is divided into two stages, light and dark stages. Glucose is always produced at the dark stage of the photosynthesis process. The light stage of the process occur during the day. In the light stage, the plant capture energy from the sun by the help of chlorophyll, the energy obtained in the day is used during the dark period to produce glucose.