What term describes optically active polyhydroxy aldehydes or ketones?

The term that describes optically active polyhydroxy aldehydes or ketones is carbohydrates. Carbohydrates are organic compounds that consist of carbon, hydrogen, and oxygen, typically in a ratio that approximates (CH₂O)n, where n indicates the number of carbon atoms.

Optical activity in carbohydrates arises because they have multiple hydroxyl (–OH) groups and a carbonyl (C=O) group, which can exist as either an aldehyde or a ketone. The presence of these functional groups results in isomerism, specifically in forms known as aldoses (with an aldehyde group) and ketoses (with a ketone group).

Monosaccharides, which are simple carbohydrates, can be optically active due to chiral centers resulting from the arrangement of their hydroxyl groups around the carbon skeleton. This optical activity is an essential property of carbohydrates, as it distinguishes between different sugar forms and plays a vital role in biological recognition processes, such as enzyme-substrate interactions.

In contrast, amino acids, proteins, and lipids do not fit the definition given in the question. Amino acids contain an amino group and a carboxyl group but lack the structure of polyhydroxy aldehyd