Why is it necessary to heat the TLC plate before utilizing it?

• A) To mark the TLC plate
• B) To saturate the jar with solvent vapors
• C) To visualize compounds
• D) To set the glass jar

How is the lower organic phase preserved after extraction during extraction of lipids

• A) Heating
• B) Sonication
• C) Evaporation
• D) Freeze-drying

What type of sugar is mainly responsible for producing a positive result in the Fehling's test?

• A) Sucrose
• B) Glucose
• C) Lactose
• D) Fructose

What is done to break the phase after homogenization during extraxtion of lipids?

• A) Adding NaCl
• B) Centrifugation
• C) Vortexing
• D) Heating

What color on the pH reagent pad indicates an acidic pH?

• A) Yellow-orange
• B) Purple
• C) Green-blue
• D) Red

In the Fehling's reaction, what is the end product formed after the reduction of copper ions?

• A) Copper sulfide
• B) Copper hydroxide
• C) Copper metal
• D) Copper oxide

How is the glycogen content calculated in the results?

• A) Total liver weight / Weight of glycogen
• B) Weight of glycogen / Total liver weight
• C) Weight of glycogen / (Weight of glycogen tube – Empty tube weight)
• D) Empty tube weight / Weight of glycogen

What safety measure is essential when working with Fehling's solution?

• A) Mix with strong acids
• B) Wear gloves and goggles
• C) Avoid boiling the solution
• D) Store in direct sunlight

In Thin Layer Chromatography (TLC), why is the adsorbent crucial?

• A) To immobilize the mobile phase.
• B) To decrease sample concentration.
• C) To minimize solvent evaporation.
• D) To facilitate sample separation.

Which term describes the non-moving phase in Thin Layer Chromatography (TLC)?

• A) Mobile phase
• B) Stationary phase
• C) Moving phase
• D) Active phase

Where is the upper aqueous phase transferred for analysis? Hint: Extraction of lipids

• A) Fresh tube
• B) Lyophilizer
• C) Original tube
• D) Orbital shaker

Which condition could potentially result in false-negative outcomes in the Fehling's test?

• A) Presence of reducing sugars
• B) High concentration of glucose
• C) Acidic pH
• D) Short boiling time

In the Fehling's test, what is the purpose of boiling the solution after adding the sample?

• A) To speed up the reaction
• B) To cool down the reaction
• C) To prevent color change
• D) To separate copper ions

Besides glucose, which of the following is also a reducing agent that can give a positive Fehling's test?

• A) Fructose
• B) Sucrose
• C) Cellulose
• D) Starch

Where is the upper aqueous phase transferred for analysis? Hint: Extraction of lipids

• A) Fresh tube
• B) Original tube
• C) Lyophilizer
• D) Orbital shaker