Ultimately it came from the sun via photosynthesis in green plants.
The electrons in the electron transport chain originate from the breakdown of glucose during cellular respiration.
C. Energy is released during cellular respiration, in the form of chemical energy.
CO2 is released as bi product.Oxygen is utilized in reaction.
kreb's cycle
oxygen
NAD is reduced during cellular respiration.
The substances that are needed for cellular respiration are glucose and oxygen. During cellular respiration, the cells convert food into usable energy.
CO2 serves as an end product that is released from body tissues (cells) after cellular respiration is used to release the energy from an ATP molecule.
Glucose
Energy
Carbon dioxide is produced during the process of cellular respiration During cellular respiration energy is released in the form of ATP. Oxygen is reduced to form water and Carbon of glucose combines with oxygen to produce carbon dioxide. Thus, carbon dioxide, water and energy are produced during cellular respiration.
NAD is reduced to NADH during cellular respiration.