Chapter 36, Problem 2Q

Summary Introduction

To review:

A genetic screening to identify the phyC –deficient mutants and the type of phenotypes examined for this screening.

Given:

It is given in the experiment that the plants in which the gene for phy C was overexpressed shows an increase in the leaf area relative to the wild type.

Table: Phtochromes phyA, phyB, phyC, and phyD were separately overexpressed in Arabidopsis, and 18-day-old seedlings were examined with regard to leaf area.

Gene expression	Leaf area (mm2)
Wild-type	22
phyA overexpressed	21
phyB overexpressed	21
phyC overexpressed	31
phyD overexpressed	22

Introduction:

The genetic screen is an important technique that can be used to identify certain genes involved in a particular function. It is an experimental technique in which individuals that possess a certain type of phenotype are identified from a mutagenized population. Genetic screens are helpful in studying functions of genes of interest.