Question

Which of the following sugars is not found in plants?
A.Sucrose
B.Glucose
C.Lactose
D.Fructose

Answer 1

Carbohydrates include both simple sugars (little ring-shaped molecules made of carbon, hydrogen, and oxygen- either alone or in pairs), as well as more complex carbohydrates which are formed when the ring links up together to make long chains. Carbohydrates provide us calories or energy and simple sugars in particular play many important roles in one's diet.

Complete answer: Sugar refers to a family of molecules called saccharides. Monosaccharides where "mono" means one. So one sugar molecule, disaccharides where "di" means two, two sugar molecules linked together, Oligosaccharide where "oligo" means few so it's three to nine sugar molecules linked together and polysaccharide where "poly" means many, so it's ten or more molecules linked together.
Option -A-Sucrose: Sucrose or table sugar is a disaccharide and it's formed when fructose links up with glucose. Sucrose is found in various fruits and vegetables, with sugarcane and sugar beets having the highest quantities. This sugar is found in both plants and animals.
Option -B-Glucose: Glucose is the most important member of the sugar family and it is a monosaccharide. It's one of the main sources of calories for the body. This sugar is also found in both plants and animals.
Option -C-Lactose: Lactose is a disaccharide. Galactose is known as milk sugar. It is known as milk sugar because it is only found in nature when it links with glucose to form lactose, a disaccharide found in the milk of mammals, which includes Cows and human breast milk. This sugar is found exclusively in animals and not in plants.
Option -D- Fructose: Fructose is commonly found in honey, fruits, and root vegetables and is a monosaccharide. It too is found in both plants and animals.
So, the correct answer to this question is an option C "Lactose"

Note: Maltose is another disaccharide and this is two glucose molecules linked together and it's found in molasses which can be used as a substrate to ferment beer. Sugars like fructose, for example, are almost always found in combination with other sugars and the combinations can be pretty different even in seemingly similar foods.