Final answer:
Life is carbon-based because carbon atoms can form stable, versatile bonds with many elements, creating a diverse array of complex organic molecules essential for life. The conditions of our solar system's formation provided the building blocks, including carbon, necessary for life as we know it.
Step-by-step explanation:
Life on Earth is carbon-based due to carbon's unique ability to form stable bonds with many elements, including itself. Carbon has four electrons in its outer shell, enabling it to form four covalent bonds. This versatile bonding allows for the creation of a vast array of compounds, including long-chain polymers essential to life. Simple organic molecules like methane (CH4), with one carbon atom bonded to four hydrogen atoms, exemplify carbon's ability to construct complex molecules. These organic molecules, primarily hydrocarbons, are the foundation of biochemistry.
Carbon is abundant in macronutrients vital to life, such as carbon, nitrogen, oxygen, and hydrogen. Additionally, many of these carbon compounds store energy, and they form the basis of macromolecules that are critical to the structure and function of living organisms.
Our solar system's formation from a gas and dust cloud, enriched with heavy elements from prior stellar generations, set the stage for chemical combinations that led to life. The presence of carbon in these combinations is crucial for the development of life, and there is a belief, based on the Copernican principle, that if life emerged on Earth, it could potentially arise elsewhere in the universe under similar conditions.