What is the group of 4 chromosomes called

The health, management and conservation of biodiversity, is a challenge facing ecosystems worldwide. the major factors that affect the health and function of the great barrier reef are climate change and pollution. which question investigates the effects of a biotic factor on the reef ecosystem?

Which represents the cross between parent plants if one is heterozygous for yellow-colored pods and the other is homozygous for green-colored pods? yy  ´    ´    ´    ´  yy

What causes darkening of the skin as melanin production increases