These are complex proteins that speed up chemical reactions by lowering the amount of energy needed to get the reaction started.

Enzymes

Explanation:

Enzymes are the complex proteins that speeds up the chemical reaction by enhancing the rate of reaction.

These proteins lowers down the activation energy and helps in carrying out the whole reaction in very less energy.

All the enzymes are proteinous in nature and they do not take part in the reaction they just speed up the reaction.

Enzymes

Explanation:

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hypoxemia refers to a below usual concentration of oxygen in the blood, mainly in the arteries. hypoxemia is an indication of an issue associated with circulation or breathing and may lead to various symptoms like shortness of breath.  

the condition is identified by determining the level of oxygen in the blood sample obtained from an artery. it can also be predicted by determining the oxygen saturation of the blood with the application of a pulse oximeter.  

the normal arterial oxygen is about 75 to 100 mm hg. the values underneath 60 mm hg is generally considered with the requirement for supplemental oxygen. the normal pulse oximeter readings generally range between 95 to 100 percent. the values under 90 percent are regarded as low.  

in the given case, the oxygen saturation is measured at 93 percent, hence, there is no need to administer oxygen, that is, one should withhold oxygen.