is all of earths carbon dioxide supply constantly being used by organisms
No, not all of Earth's carbon dioxide supply is constantly being used by organisms. Carbon dioxide (CO2) is a key component of the carbon cycle, which involves the movement of carbon between the atmosphere, land, ocean, and living organisms. While some organisms, such as plants and photosynthetic bacteria, use CO2 for photosynthesis and convert it into organic matter, the amount of CO2 used by organisms is not equal to the total supply of CO2 on Earth.
A significant portion of Earth's carbon dioxide supply remains in the atmosphere, contributing to the greenhouse effect and climate change. Additionally, carbon dioxide is dissolved in seawater and plays a crucial role in regulating the pH of the oceans. Moreover, geological processes, such as volcanic activity and weathering of rocks, also release carbon dioxide into the atmosphere.
Overall, the carbon dioxide supply on Earth is part of a dynamic system where it is continuously exchanged between different reservoirs, including the atmosphere, oceans, land, and organisms.