Question

1. below the food samples label, drag tube a into the food sample holder. below the benedict test, click the test button. what is done in the benedict test?
2. the benedict test is a test for monosaccharides; simple sugars like glucose or fructose (fruit sugar). in contact with monosaccharides, the benedict solution turns from blue to green to orange.

does sample a contain monosaccharides?
note: disaccharides such as sucrose (table sugar) and lactose (milk sugar) are more complex than monosaccharides. the benedict test does not detect disaccharides directly.
activity a:
identifying nutrients
get the gizmo ready:

• click reset.
• drag sample a into the food sample holder.

introduction: most food is composed of three types of molecules: carbohydrates, proteins, and lipids.

• carbohydrates such as starches and sugars are major source of energy. simple sugars are found in sweets and fruits. starches are found in potatoes, cereal, pasta, flour, and other plant products.
• proteins are used in body structures such as muscles, skin, and hair. rich sources of proteins include meats, dairy products, and beans.
• lipids (fats and oils) are used for energy, insulation, and as an essential building block of cells. meats, dairy products, and oily plants such as olives are rich in lipids.

question: how do you test for carbohydrates, proteins, and lipids? (2 marks)

Explanation:

To test for carbohydrates, proteins, and lipids, specific tests are used. For carbohydrates (monosaccharides), the Benedict's test is employed. Benedict's solution reacts with monosaccharides, changing color from blue to green to orange. For proteins, the Biuret test is used; it turns violet in the presence of proteins. For lipids, the Sudan III or IV test is utilized; lipids will stain red with these reagents.

Answer:

To test for carbohydrates (monosaccharides), use Benedict's test (color change from blue - green - orange if monosaccharides are present). For proteins, use the Biuret test (violet color indicates proteins). For lipids, use Sudan III/IV test (red color shows lipids).