Which of the following is not necessary for respiration?
a) quinones
b) cytochromes
c) a source of electrons
d) flavoproteins
e) oxygen

The right answer is surprisingly E.

Quinones, flavoproteins, cytochrome c, and electrons are important elements, essential for the respiratory chain.

Oxygen in respiration plays a role of final acceptor of electrons (and turns into H2O), but there are other final acceptors of electron transport depending on the species (nitrates for Pseudomonas, Sulphites for Clostridium ...). This allows us to classify respiration in two: aerobic respiration (with oxygen) and anaerobic respiration (without oxygen but with another electron end acceptor).

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.

c. live where it’s cold and icy