In later chapters, you will learn more about the regulation of gene expression. one way to regulate gene expression is to make changes to the histone proteins to alter how tightly the dna is coiled and wrapped. the more tightly coiled and wrapped a particular region of dna is, the less likely it is that the genes in that region will be expressed. bearing this in mind, how tightly do you think regions of heterochromatin are compacted?
a, because natural selection can only act upon existing traits. if there is no genetic variation and there is only one trait, then there's no favoring 'for' or 'against' phenomenon. genetic variation equates to many different traits being present in a population, so natural selection can pick out which traits are the best by increasing the frequencies of those traits that allow the organism to live longer and reproduce more.
the plants also have the growth hormones which improves the production of plants cells, increase fruits and develop more roots of the plants. the five major growth hormones present in kelp products contains auxins, cytokinins, gibberellins, ethylene, and abscisic acid. auxins are responsible for stimulating the growth in immature parts of the plants. these growth hormones responsible for the acceleration of growth of leaves, fruits, and roots of the plants.