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Mutations
These mistakes are called mutations, from Latin word meaning " to change ".
8) Mutations are changes in the genetic material.
Kind of Mutations
Gene mutations involving changes in one or few nucleotides are known as point mutations because they occur at a single point in the DNA sequence.
Changes like these are called frameshift mutations because they shift the reading frame of genetics message.
The condition in which an organism has extra sets of chromosome is called polyploidy.
Lesson 5
Gene Regulation
Gene Regulation: An Example
A group of genes that operate together is known as an operon.
9) The lac genes are turned off by repressors and turned on by the presence of lactose.
The other region is the operator (O).E. coli cells contain several copies of a DNA-binding protein known as the lac repressor, which can bind to the O region.
Eukaryotic Gene Regulation
10) Most eukaryotic genes are controlled individually and have regulatory sequence that are much more complex than those of the lac operon.
Developmentt & Differentiation
This means that cells don't just grow & divide during embryonic development; they also undergo differentiation, meaning they become specialized in structure and function.
A series of genes, known as the hox genes, control the differentiation of cells and tissues in the embryo.
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