Muscle fibers are arranged in bundles called tendons
<em><u>Answer:Anatomically, respiratory tract is divided into upper (organ outside thorax - nose, pharynx and larynx) and lower respiratory tract (organ within thorax - trachea, bronchi, bronchioles, alveolar duct and alveoli). The discussion is mainly concentrated on the lower respiratory tract and the related physiology.</u></em>
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1) The first reactant is incomplete.
2) The reaction is a combustion reaction and it is easy to infere that it is the combustion of the alkane with 3 carbons.
3) The general chemical formula of the alkanes is

4) Hence the equation is:

5) The name of the alkane is propane, so the word equation is:
propane + oxygen → carbon dioxide + water
6) The equation is unbalanced. This is the balanced equation:

7) It is, as the combustion of any hydrocarbon, a redox (reduction-oxidation) reaction, where the carbon is oxidized and the oxygen is reduced.
8) This kind of reactions release a lot of energy.
Answer:
Hey i think there is an error in ur question, u may recheck the so called word "metopus"
But here is the definition of Endosymbionts are organisms that form a symbiotic relationship with another cell or organism