Question

Platelets are extracted from plasma by the process

• A. Autoclave
• B. Filtration
• C. Dialysis
• D. Centrifuge

Hint:

Centrifugation is a key method for separating components of blood, such as platelets, based on their density.

Answer 1

The Correct Option is D

Step 1: Understanding platelet extraction.
Platelets are typically extracted from plasma by a centrifugation process, which allows the separation of different blood components based on their density. Platelets form a pellet at the bottom, separated from the plasma.
Step 2: Analyzing the options.
(1) Autoclave: Incorrect, autoclaving is used for sterilization, not for separating platelets.
(2) Filtration: Incorrect, filtration is not commonly used for platelet extraction.
(3) Dialysis: Incorrect, dialysis is used to separate molecules based on size, not for platelets.
(4) Centrifuge: Correct — Centrifugation is the method used to extract platelets from plasma.
Step 3: Conclusion.
Platelets are extracted using (4) Centrifuge.

Answer 2

Separating platelets from plasma relies on a physical property that distinguishes them from other blood components. Let's check each option against this.

1. Autoclave: Autoclaving uses high-pressure steam to sterilize equipment or materials; it destroys cells and cannot be used to isolate living platelets.
2. Filtration: Filtration separates particles based on size using a membrane, but platelets and plasma proteins can be similar enough in size that simple filtration is not the standard method used for this separation.
3. Dialysis: Dialysis separates small molecules from large ones across a semipermeable membrane, based on diffusion, which is not how cellular components like platelets are isolated.
4. Centrifuge: Centrifugation separates blood components based on differences in density, spinning the sample so that heavier platelets settle out from the lighter plasma, which is the standard method used to isolate platelets.

Only centrifugation exploits the density difference needed to separate platelets from plasma.

Therefore, the correct answer is Centrifuge.