The correct answer to this question is this one: they lacked oxygen. The earliest organisms were completely heterotrophic in nature because of the reason that they lacked oxygen. <span>A heterotroph is an organism that cannot fix carbon and uses organic carbon for growth. </span>
They are both the building blocks of life
Growth is defined as the irreversible increase in the dry mass of an organism. It is brought about by an increase in cell size or number. In plants, growth occurs throughout the lifetime of the plant. ... Plants have extensive powers of regeneration. They can replace lost or damaged tissue.
Rods work very well in darkness/ low light. Cones process colors.
The correct answer for this question is D - lipids. Lipids are also
known as fat, and are useful not only as protection, but also as long
term storage for energy, protection for vital organs. A certain type of
lipid even assists with communication between cells.
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