0
What else can I help you with?
Why glucose does not give positive result with iodine test but not starch?
Glucose does not give a positive result with the iodine test because iodine specifically binds to the helical structure of amylose, a component of starch, forming a blue-black complex. Glucose, being a monosaccharide, does not possess this helical structure, and therefore does not interact with iodine in the same way. In contrast, starch, which is a polysaccharide made up of multiple glucose units, presents the necessary structure for the iodine to react and produce a visible change.
How can you tell if glucose starch water and iodine passes through the cell membrane?
If the glucose, starch, and iodine pass through the cell membrane, you can perform a color change test. The presence of glucose will show a positive result with Benedict's reagent turning orange/red. The presence of starch will show a positive result with iodine turning blue/black.
Is fehling test positive for gluconic acid?
No. Fehling's test is positive for glucose which forms gluconic acid as the product.
What reagent is used to test for glucose and starch?
Benedict's solution is used to test for glucose, turning from blue to orange-red in the presence of reducing sugars. Iodine solution is used to test for starch, producing a blue-black color in the presence of starch.
What is used to test for presence of polysaccharide?
Most likely the sucrose test. what biologist use is the iodine test. Iodine is used to test for the presence of starch( a polysaccharide) any material containing starch always turn blue-black when iodine is added.
Why glucose does not give positive result with iodine test but not starch?
Glucose does not give a positive result with the iodine test because iodine specifically binds to the helical structure of amylose, a component of starch, forming a blue-black complex. Glucose, being a monosaccharide, does not possess this helical structure, and therefore does not interact with iodine in the same way. In contrast, starch, which is a polysaccharide made up of multiple glucose units, presents the necessary structure for the iodine to react and produce a visible change.
Why did a solution of saliva and oats test positive with benedict's test and iodine test if the oats alone tested positive only in the iodine test and the saliva alone was negative for both?
Saliva contains the enzyme amylase which breaks down starches in oats into simple sugars like glucose, which can then react with Benedict's solution to give a positive test result. The iodine test detects the presence of starch, which is in oats but not in saliva, explaining why the combination tested positive in both tests.
What is positive color for iodine test?
The positive color for the iodine test is a dark blue or black color. This color change indicates the presence of starch in the test substance.
Do proteins give positive iodine tests?
Yes, proteins can give a positive iodine test. When iodine reacts with proteins, it forms a complex that results in a brown color change, indicating a positive test for proteins.
Is there a method for detecting starch without using iodine?
Yes, you can detect starch using enzymes like amylase to break down the starch into simpler sugars, and then test for the presence of those sugars using a glucose test strip or a colorimetric assay. This method is often used in laboratories as an alternative to iodine staining.
How can you tell if glucose starch water and iodine passes through the cell membrane?
If the glucose, starch, and iodine pass through the cell membrane, you can perform a color change test. The presence of glucose will show a positive result with Benedict's reagent turning orange/red. The presence of starch will show a positive result with iodine turning blue/black.
Is iodine an indicator of glucose?
Iodine is not an indicator of glucose. Iodine is primarily used as an indicator for the presence of starch in a solution through the formation of a blue-black color complex. Glucose can be tested using methods such as Benedict's solution, Fehling's solution, or glucose test strips.
Why would a negative iodine test for starch indicate a positive result for the enzymatic degradation of starch by amylase?
A negative iodine test for starch indicates that the starch has been broken down by amylase into simpler sugars, such as maltose or glucose, that do not react with iodine. Therefore, the absence of a starch-iodine complex formation suggests that amylase has successfully degraded the starch substrate.
Iodine and Benedict's solution were both used to test for certain nutrients in a sample of food If both tests were positive for the nutrients the sample must contain?
Both iodine and Benedict's solution test for different nutrients in the sample. Iodine is used to test for the presence of starch, while Benedict's solution is used to test for the presence of reducing sugars like glucose. Therefore, if both tests are positive, the sample must contain both starch and reducing sugars.
What color is positive test result for glucose?
the color of a positive test results is bright green
Is fehling test positive for gluconic acid?
No. Fehling's test is positive for glucose which forms gluconic acid as the product.
Why doesn't cellulose give a positive iodine test?
cellulose is derived from D-glucose units, which condensed through beta(1->4)-glycosidic bond. This give cellulose to be a straight polymer therefore, it can't coil around iodine to produce blue color as starch does.
