We inhale oxygen when we breath and exhale CO2. What is the oxygen used for and where does the CO2 come from? a) The oxygen is used during the electron transport phase of cellular respiration. The CO2 we exhale is formed during the citric acid cycle when the bonds in carbon compounds are broken.
b) The oxygen is used as an energy source for our cells. The CO2 is produced by the ATP synthase.
c) The oxygen is used during glycolysis to break down glucose. CO2 is produced as glucose is broken down.
d) The CO2 is used during electron transport as a final electron acceptor. Oxygen is produced during the citric acid cycle.

Every compound can be represented by a chemical formula. a chemical formula is the set of symbols showing the elements that make up a compound and their proportions. water’s chemical formula is h 2 2 o. that means a molecule of water contains two atoms of hydrogen and one atom of oxygen chemically bonded. a molecule is a group of two or more atoms bonded together. molecules can range in size from two to thousands of atoms. a molecule of a compound is the smallest unit of that compound. every molecule of water has all the physical and chemical properties of water. that’s because every molecule of water is made of the same elements in the same proportions: two hydrogen atoms and one oxygen! which of the following is a true statement? a every molecule of the same compound will have different properties. b every molecule of a compound has the same proportion of elements. c molecules can be physically separated into smaller units of a compound. d molecules cannot be represented by chemical formulae.

What did the first language sound like

What happens when the cell copies its chromosomes