As electrons are passed down the electron transport chain, the molecules are first as they pick up electrons, and then as they release the electrons.

reduced; oxidized

Explanation:

An electron transport chain can be defined as a series of redox reactions (electron transporters or proton complexes) that are saddled with the responsibility of transferring electrons from electron donors to electron acceptors through a membrane in order to produce a protein gradient that creates energy or adenosine triphosphate (ATP).

Generally, as these electrons are transferred through the electron transport chain, the molecules are first reduced as they pick up electrons, and then oxidized as they release the electrons.

Cellular respiration can be defined as a series of metabolic reactions that typically occur in cells so as to produce energy in the form of adenosine triphosphate (ATP). During cellular respiration, high energy intermediates are created that can then be oxidized to make adenosine triphosphate (ATP). Therefore, the intermediary products are produced at the glycolysis and citric acid cycle stage.

Additionally, mitochondria provides all the energy required in the cell by transforming energy forms through series of chemical reactions; breaking down of glucose into Adenosine Triphosphate (ATP) used for providing energy for cellular activities in the body of living organisms.

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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