Which one of the following is a single membrane structure?

Options

(a) lysosomes
(b) chloroplast
(c) mitochondria
(d) nucleus

Correct Answer:

lysosomes

Explanation:

A lysosome is a tiny sac bounded by a single unit membrane of lipoprotein discovered by de Dube (1995). It contains a dense, finely granular fluid. The latter consists of glycoprotein hydrolytic (digestive) enzymes called acid hydrolases. These include proteases, lipases, nucleases, glycosidases, sulphatases, acid phosphatases, etc. However, all the enzymes do not occur in the same lysosomes. The lysosome enzymes do not occur in the same lysosome. There are different sets of enzymes in different lysosomes. The lysosome enzymes can break down all major biological macromolecules present in the cells or entering the cells from outside into their building block subunits by addition of water. So these are digestive in nature. The lysosome enzymes are active in acid medium, at about pH 5, hence their name. It is also called suicidal bag.