Tuesday, September 9, 2008

Homework Questions 1-12, 14, 15


b. sucrose
b. carbohydrate
c. hydrophilic
b. lipid.
b. side groups
d. substrate
b. cools a reaction, slowing it down


8.) Besides satisfying your hunger, why else might you consume a big bowl of pasta the night before a race?
You might also consume a big bowl of pasta the night before a race because
pasta is composed of carbohydrates which store the energy in your body for a long period of time, allowing more energy in the upcoming race.
9.) How are glucose, sucrose and starch related?
Glucose, sucrose and starch are related because they are allpolysaccharides which are a type of carbohydrates and they are all a type of sugar.
10.) What are steroids? Describe two functions they have in cells.
Steroids are lipid molecules in which the carbon skeleton forms four fused rings. Steroids are a hydrophobic substance that circulate your body as chemical signals as well as acting as membranes that surrounds different cells.
11.) How are polypeptides related to proteins?
Polypeptides are related to proteins because proteins are made up of one or more polypeptides chains which are linked together into amino acid chains.
12.) How does denaturation affect the ability of a protein to function?
Denaturation affects the ability of a protein to function because if a protein is located in an unfavorable environment, some including a variety of change in pH, temperature or other issues of heat, the protein may unravel and lose its normal shape. Some examples of denaturation include frying an egg as the egg white changed from a clear liquid to a white solid during cooking because heat denaturates the egg's proteins.
14.) a The molecule represented by a question mark is a water molecule that has been removed during the chemical reaction of dehydration between two amino acids as they join together. Each time amino acids are added to a chain, a water molecule is removed.
b. This reaction is called a dehydration reaction because it involves removing (de) water (hydro). Each time a monomer is added to a chain, a water molecule is released. Same thing happends when a monomer is released, water is added to break it down.
c.If an amino acid were added to this chain, it can attach itself to the OH of the reaction or the H on the other end of the reaction.

15. ) a. Enzyme A performs the best at around 38 degrees Celsius and Enzyme B performs the best at 78 degrees Celsius.
b..Enzyme A is found in humans and enzyme B is a thermophilic enzyme.
c. If the rate of the reaction catalyzed by enzyme A slows down at temperatures about 40degrees Celsius, then the reaction will continue to slow down and become short.