purifikasi protein dan teknik pemisahannya

Open Ended

Describe how the ability to purify a specific protein from thousands present in a cell can impact scientific understanding or medical applications.

Multiple Choice

Which of the following is NOT a reason for protein purification?

• To determine amino acid sequence

• To study biochemical function

• To analyze protein evolution

• To increase protein solubility

Open Ended

Explain how the specificity of an assay affects the effectiveness of protein purification.

Multiple Select

Which statements about lactate dehydrogenase assay are correct?

• NADH absorbs light at 340 nm

• NAD+ absorbs light at 340 nm

• The assay monitors purification process

• Enzyme activity is measured by decrease in absorbance

Fill in the Blanks

Specific activity is defined as enzyme activity divided by

.

Open Ended

Describe the initial steps required to obtain a crude extract from cells for protein purification.

Multiple Choice

During differential centrifugation, which cellular component is separated at 10,000×g?

• Nucleus

• Mitochondria

• Microsomal fraction

• Cytoplasm

Open Ended

Explain how the concentration gradient is involved in the process of dialysis for protein separation.

Multiple Choice

Which method uses a semipermeable membrane to separate proteins from small molecules such as salts?

• Dialysis

• Column Chromatography

• Electrophoresis

• Centrifugation

Multiple Choice

Column chromatography separates proteins based on which of the following properties?

• Charge, size, binding affinity, chemical properties

• Only size

• Only charge

• Only chemical properties

Open Ended

Describe the role of the mobile phase and stationary phase in the separation of proteins during column chromatography.

Fill in the Blanks

Fill in the blank: In column chromatography, the stationary phase is a solid,

matrix.

Multiple Choice

Which protein band in column chromatography moves the fastest and why?

• Band A (Blue), because it has the weakest interaction with the stationary phase

• Band B (Red), because it has moderate interaction with the stationary phase

• Band C (Green), because it has the strongest interaction with the stationary phase

• Band A (Blue), because it has the strongest interaction with the stationary phase

Multiple Choice

Which factor increases the resolution in protein separation using column chromatography?

• Increasing column length

• Decreasing column length

• Increasing protein concentration

• Decreasing temperature

Open Ended

Explain how band broadening (peleburan pita) affects the separation of proteins in column chromatography.

Multiple Choice

Which of the following can be adjusted to control elution in ion exchange chromatography?

• pH

• Temperature

• Pressure

• Light intensity

Open Ended

Describe the difference in movement of peptides with different net charges in cation and anion exchangers.

Fill in the Blanks

In ion exchange chromatography, a cation exchanger binds to proteins with

charge.

Multiple Choice

In size-exclusion (gel filtration) chromatography, which type of protein will elute first from the column?

• Large proteins

• Small proteins

• Proteins with high charge

• Proteins with low charge

Open Ended

Reflecting on today's lesson, what questions do you still have about protein purification or its separation techniques?

Multiple Choice

Why is protein purification important in biological research?

• To study the chemical and physical properties of proteins

• To test the biological activity of proteins

• To increase the number of proteins in a cell

• To separate a specific protein from thousands present in a cell