The element found in every living thing is primarily carbon, along with hydrogen, oxygen, and nitrogen. These four elements-carbon (C), hydrogen (H), oxygen (O), and nitrogen (N)-are essential to all known life forms and collectively make up about 96-99% of the mass of living organisms' protoplasm

. More specifically:

• Carbon is the central element in organic molecules, forming the backbone of carbohydrates, proteins, lipids, and nucleic acids due to its ability to form four covalent bonds

• Hydrogen is a key component of water and organic molecules, essential for biochemical reactions

• Oxygen is abundant in water and organic molecules and is critical for cellular respiration and energy production

• Nitrogen is fundamental in amino acids and nucleic acids, vital for proteins and genetic material

Together, these elements are often referred to as the bulk elements essential for life. In addition, phosphorus and sulfur are also common essential elements found in all living things, important for nucleic acids and amino acids respectively, but carbon, hydrogen, oxygen, and nitrogen are universally present in every living organism

. In summary, carbon is the key element found in every living thing, along with hydrogen, oxygen, and nitrogen, forming the chemical basis of life on Earth.