The inspiratory reserve volume measures the
amount of air remaining in the lung after a maximal exhalation
amount of air that the lung holds
amount of air the can be further exhaled after a normal breath
amount of air that can be further inhaled after a normal breath

Amount of air that can be further inhaledafter a normal breath

Explanation:

The medical definition for inspiratory reserve volume or IRV is: "Amount of air that can be further inhaled after a normal inhalation".

As a color date, the mean IRV for adult men is 3.1lt, meaning more than the 50% for the lung capacity!

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure