Carbohydrates video review
This video gives a general overview of carbohydrates. It starts off giving the roles of carbohydrates and then it goes into the structure of it. It basically states that carbohydrates are divided into two categories simple sugars and polysaccharides. The major functions of carbohydrates are: it is used as an energy source and it provides structural integrity especially in the cell wall of plants through cellulose. The formula for carbohydrates suggests that there is a 1:2:1 ratio of 1 carbon atom to 2 hydrogen atoms to 1 oxygen atom. For example pentose, has 5 carbons and will therefore have the formula C5H10O5.
There are four types of Carbohydrates:-
- Monosaccharides-simple sugars comprising of a single sugar unit. Monosaccharides can be represented either in the ring or linear form. When the hydroxyl group in the ring form is below the molecule it is referred to as an alpha- glyceride, when it is below, it is referred to as a beta- glyceride. Monosaccharides are given their names based on the number of carbons they contain. Eg.Triose- 3 carbons C 3H 6O3 ,Tetrose- 4 carbons C 4H8 O4
- Disaccharides consist of two monosaccharides joined by a glycosidic bond. Formation of the glycosidic bonds results in the loss of a water molecule (condensation).
- Oligosaccharides consist of 3-20 sugar molecules bonded together.
- Polysaccharides are molecules consisting of several sugars bonded together to form a large complex molecule. The 3 main polysaccharides are cellulose, Glycogen and Starch.
Cellulose- A major constituent of plant cell walls, which has a linear glucose polysaccharide chain and contains the beta-(1-4) bonds responsible for strength and rigidity of the plant cell wall.
Starch- The form in which plants store their carbohydrates. It comprises several glucose molecules and the main form of starch is amylopectin that has both alpha- (1-4) and alpha – (1-6) bonds.
Glycogen- Animals and humans store glucose/carbohydrates in the form of glycogen in the liver and skeletal muscles.
This is a good video for students who want to learn the basics of carbohydrates because it doesn’t go into great detail. On the other hand, the video is very informative and the narrator knows how to relate his work to others.
“Carbohydrates.” Accessed February 9,2014.http://www.salmonellaplace.com