Why are you saying that carbon is needed to make starch? Actually only sugar (glucose) is needed along with an enzyme to catalyze the linkage of multiple glucose units in a dehydration (loss of water) reaction.

Glucose + Glucose ----> maltose + H2O

maltose is disaccharide.

maltose + glucose ----> maltotriose + H2O

maltotriose is a trisaccharide (has three sugars hooked together)

This keeps going on and on with four sugars, five sugars, six sugars... until there are hundreds of glucose units hooked together. Then one has starch.

Im confused! heres the exact question the teacher asked.

Describe how sugars combine to form starch. Carbon seems to be an essential componet of sugar and sugars combine to form starch. How does that happen? You may use illustrations to answer this question. Do not go into great detail. A brief summary of the process will suffice.

Do you think you can help? thanks

The formula for glucose is C6H12O6.

The carbon is a component of the glucose molecule. Carbon, per se, is not used to form starch. Actually, one could argue that hydrogen and oxygen and are essential components too. The formula for maltose is C12H22O11. As explained previously, two glucose units are combined to form

C6H12O6 + C6H12O6 ----> C12H22O11 + H2O

C12H22O11 = maltose.

If you add up all the carbons, hydrogens, and oxygens on both sides of the reaction above, they will total 12 carbons, 24 hydrogens, and 12 oxygens.

Now, if another glucose is combined with maltose, maltotriose is obtained.

C12H22O11 + C6H12O6 ----> C18H32O16 + H2O

Do a Google search on the phrase "Three common sugars share the same molecular formula" and click on the first link. Look at the section on polysaccharides.

I apologize for the confusion. I misunderstood the question initially. You are correct that carbon is a component of the glucose molecule, not an ingredient used specifically to form starch. Thank you for clarifying that.

To answer the question about how sugars combine to form starch, let me provide a brief summary:

Starch is a polysaccharide, which means it is made up of many sugar units linked together. Specifically, starch is composed of glucose units. The process of combining sugars to form starch involves the dehydration (loss of water) reaction you mentioned earlier.

Glucose molecules can be joined together through a process called condensation or dehydration synthesis. In this reaction, a molecule of water is removed as two glucose molecules become linked together. This results in the formation of a disaccharide called maltose, as you mentioned earlier.

To continue the process, additional glucose molecules can be added to the existing maltose molecule through the same condensation reaction. This leads to the formation of trisaccharides, like maltotriose, when three glucose units are hooked together.

The process can continue, with more and more glucose units being added to the chain, until there are hundreds of glucose units linked together. This long-chain structure is what constitutes starch.

Therefore, to summarize:

1. Glucose molecules are combined through a condensation reaction, which removes a molecule of water.
2. This results in the formation of disaccharides and further addition of glucose units leads to the formation of trisaccharides and longer chains.
3. The process continues until a large number of glucose units are linked together, forming starch.

For additional information and illustrations, I suggest searching for "starch formation" or "how glucose units combine to form starch" to find resources that can provide more detailed explanations and visual aids.