Monday, September 1, 2008

5.2 Summary...


Section 5.2
This section mainly discusses the important CARBOHYDRATES that provide living things energy or “fuel”.
Carbohydrates are organic compounds that are made up of sugar molecules. Sugar molecules are molecules that contain carbon, hydrogen and oxygen, in a ratio of 1:2:1.Since sugar molecules are the fuels for our cellular work, it is very important to take in enough carbohydrates everyday.

Glucose, fructose and galactose are monosaccharides, a sugar unit that simple sugars contain, they are found in many sweet things we eat. After a dehydration process, the monosaccharides will become a disaccharide which can be stored in the body for later use.

Starch is a polysaccharide, or long polymer chains made up of simple sugar monomers, found in plant cells and are made up of glucose monomers.
Glycogen is also a type of polysaccharide, but it is found in animals and it gives the human body energy after it’s broken down.
Cellulose, another type of polysaccharides in plants are the building material of plants. Humans and animals find it hard to digest this, so it passes though our digestive system without changing.

*Almost all carbohydrates are hydrophilic.

Concept Check 5.2
Explain the difference between a monosaccharide and a disaccharide.

The difference between a monosaccharide and a disaccharide is that a monosaccharide is made up of only 1 sugar unit, while a disaccharide is made up of many sugar monomers.
Compare and contrast starch, glycogen, and cellulose.

Starch consists entirely of glucose monomers, and are used as food for humans, glycogen is more highly branched than starch and is stored as granules for later energy use. Cellulose is the building material, it also keeps the digestive system healthy.
How do animals store excess glucose molecules?

Animals store excess glucose molecules because it is the main fuel supply for cellular work. Also glucose molecules that are not used immediately can be incorporated into larger carbohydrates or used to make fat molecules.

That’s all for this section:)

1 comment:

Anonymous said...

put pictures katie~~