Question

Which of the following centrifugation is used to separate certain organelles from whole cell?

(a) Rate-zonal centrifugation

(b) Normal centrifugation

(c) Differential centrifugation

(d) Isopycnic centrifugation

The question was asked in exam.

This is a very interesting question from Centrifugation in section Unit Operations of Bioprocess Engineering

Answer 1

Right option is (c) Differential centrifugation

Easy explanation: The simplest form of separation by centrifugation is differential centrifugation, sometimes called differential pelleting. Particles of different densities or sizes in a suspension will sediment at different rates, with the larger and denser particles sedimenting faster. These sedimentation rates can be increased by using centrifugal force. A suspension of cells subjected to a series of increasing centrifugal force cycles will yield a series of pellets containing cells of decreasing sedimentation rate.

Differential centrifugation is a common procedure in microbiology and cytology used to separate certain organelles from whole cells for further analysis of specific parts of cells.