Answer: The correct option is <span>a long carbon and hydrogen chain and a carboxyl group.
Reason: Fatty acid is basically consists of two main parts:
a hydrocarbon tail connected with carboxylic group as shown in the figure.</span>
Cells that have no mitochondria are unable to convert oxygen into energy, found in the form of adenosine triphosphate (ATP). All multicellular eukaryotic organisms, including plants and animals, have mitochondria in some cells, but prokaryotes and some single-cell eukaryotes do not have mitochondria.
The answer is whales. In the Antartic and Arctic regions, krills and whales are very abundant in numbers. Whales are number one consumer of krills in these regions. They can feed on a large swarm of krills when they feed. They also have less competition on these icy waters. They gain energy every time from eating them.
RNA has great capability as a genetic molecule; it once had to carry on hereditary processes on its own. It now seems certain that RNA was the first molecule of heredity, so it evolved all the essential methods for storing and expressing genetic information before DNA came onto the scene.