Answer:
c.building immunity towards diseases
Answer: they allow air to enter lungs and also permits air into the body
Explanation:
The correct answer is: A) lactic acid.
During the exercise, muscle cells use anaerobic respiration in order to make enough energy in the form of ATP. Anaerobic respiration doesn’t require oxygen, but glucose is broken down to produce energy. Glucose is broken down to pyruvate in the process called glycolysis. Next step is convert of pyruvate into lactic acid (or lactate).
During the exercise, the oxygen level in muscle cells decreases, which results in anaerobic respiration of the cells.
Many theories can never be proven.
Here are a few examples:
-- The moon orbits the Earth.
-- Gravity pulls all masses toward each other.
-- The Earth orbits the sun.
-- Everything is made of atoms and molecules.
-- Atoms are made of protons, neutrons, and electrons.
-- Electrons moving through a wire make electric current.
-- The center of the Earth is molten iron and nickel.
-- The source of the sun's energy is nuclear fusion in its core.
-- Almost all galaxies are moving away from us.
-- The universe is expanding.
None of these statements can be proven. That's why they're not called
Facts or Laws.
It also tells you that some pretty powerful stuff has been done with concepts
that can't be proven. If you want to make an idea look foolish, that doesn't
happen when you say "it's only a theory".
