class switching

class

1. a group of similar objects or values selected as a part of a classification.

2. a taxonomic category subordinate to a phylum and superior to an order.

3. a group of variables all of which show a value falling between certain limits.

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class action

an exemplary court case fought on behalf of a number of litigants who can expect to be treated in the same way as the contesting litigant.

class limits

the highest and lowest values eligible to be included in a class when data are being classified or grouped.

class mark

the value selected to represent all of the values in a class. It may be the median or average value.

class midpoint

the average of the upper and lower limits of a class.

class switching

when a B lymphocyte changes over from producing one type of immunoglobulins to another.

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class switching

Physiology A step in the normal maturation of Hb during fetal development that requires switching from embryonal zeta chain, which is structurally similar to the α chain, and occurs on chromosome 16 to mature α chain production; β chain production is a 2-stage maturation process with early loss of the ε chain and the presence during fetal and early post-natal life of a γ chain, which ↓ as β chain expression is ↑. Cf Introduction to this volume: note.