Homework Help

Assume that the glucose levels of the patient are high.A women thrives on a diet of...

user profile pic

cassielargy | Student, Undergraduate | Honors

Posted August 6, 2012 at 10:37 PM via web

dislike 1 like
Assume that the glucose levels of the patient are high.

A women thrives on a diet of fruit jam, bread n pasta .At her check up her her doctor recommends that she take the Benedict's test. (assume glucose levels are high)

  • State the results that the test would indicate (specify the color of the solution).



  • State the composition and the properties of the ketohexose derived from fruit jam.



  • Describe the manner in which ketohexose acts as a reducing sugar in the test.

2 Answers | Add Yours

user profile pic

sanjeetmanna | College Teacher | (Level 3) Assistant Educator

Posted August 15, 2012 at 10:52 PM (Answer #1)

dislike 1 like
  • State the results that the test would indicate (specify the color of the solution).

Urine-Benedict's test.

blue-sugar absent;

green-0.5% sugar;

yellow-1% sugar;

orange-1.5% sugar;

brick red-2 % or more sugar.

The color sequence for increased reducing sugar Benedict's test is green, yellow, orange, red, brown

brick-red precipitate indicates presence of the aldehyde group.

  • State the composition and the properties of the ketohexose derived from fruit jam.

Ketohexose is a 6-carbon monosaccarhide with ketone functional group, produced along with glucose when sucrose is hydrolyzed. It is found in fruit, honey etc., Example Fructose also known as fruit sugar found in many plants.

  • Describe the manner in which ketohexose acts as a reducing sugar in the test.

Benedict's solution composed of sodium citrate, sodium carbonate and cupric sulfate. The cupric ion is reduced to cuprous ion by the aldehyde group in the reducing sugar, and precipitates as cuprous oxide(Cu2O) forming colours depending upon the sugar concentration.

Sources:

user profile pic

cassielargy | Student, Undergraduate | Honors

Posted August 26, 2012 at 2:23 AM (Answer #2)

dislike 0 like

The Benedict's test indicate a high level of reducing sugar in the urine (sugar is also known as glucose). indicates hyperglycemia (diabetes), Benedict's reagent contains blue copper ions (Cu2+) which are reduced to copper (Cu+) in the presence of reducing sugars. These are precipitated as red copper (I) oxide which is insoluble in water. The color would be red.

A ketohexose is a simple carbohydrate with six carbon atoms as well as a ketone group which is located on the second carbon atom. It is the sweetest of the simple carbohydrates.

The solution used in the Benedict’s test is a basic solution containing sodium citrate, sodium carbonate, and copper sulfate that changes color (blue, yellow, orange, and red) in the presence of reducing sugars.

When the or ketal hydroxyl or hemi-acetal group is free (isn’t locked) and not linked to another molecule (like sugar for example) the aldehyde (or keto-) form (i.e. the chain-form) is available for reducing copper (II) ions. After the sugar is oxidized, its carbonyl group (also known as aldehyde or ketone group) is converted to a carboxyl group.

She would benefit from a diet customized for her specific diabetes and could be treated with insulin.

 

                                                                       

 

 

Sources:

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes