The correct answer is B. Oxygen.
Oxygen, as a part of the atmosphere, also participates in UV protection, besides being necessary for breathing.
Living organisms use two major types of energy storage. Energy-rich molecules such as glycogen and triglycerides store energy in the form of covalent chemical bonds. Cells synthesize such molecules and store them for later release of the energy.
Answer:
In the most common forms of oculocutaneous albinism, both parents must carry the albinism gene for a child to be born with the condition. Even if both parents carry the gene, the chance of each of their children being born with albinism is one in four.
Nicotine, once in the brain, will work specifically on nicotinic receptors in the brain. However, there is a common "addiction" pathway in the brain that pretty much all addictive substances go through.
Yes, while multicellular organisms remove waste through the urinary system, single celled organisms expel their metabolic waste with vacuoles