Why are accessory pigments like carotene & xanthophyll necessary to have in
green plants? what advantage do they provide

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.

1 and 6 for apex

the answer would be 2, if crossing over doesn’t occur 2 out of 4 of the daughter cells will have that allele.

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