Afutile cycle is a futile cycle is two opposing cellular reactions that are independently controlled two reactions or pathways that share substrates and products, and result in no net gain of atp the citric acid cycle an endergonic reaction that uses up atp

The suitable answer to the given blank is

Two reactions or pathways that share the substrate or products and result in no net gain of ATP.

Explanation:

A futile cycle can be defined as those cycles which are involved in metabolism at cellular level to control or regulate biochemical pathways.

It is also known as substrate cycle and is when two metabolic pathways follow directions opposite to each other so that the overall effect is zero other than to dissipate energy.

Therefore, the result is zero net gain.

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.