Gene Environment Interactions

Effect of the environment on gene interactions External environmental factors can modify the phenotype coded by genes. This can occur in the development of the embryo or later in life. Genotype Phenotype Environment

Activity Think of examples for the following: Temperature Altitude Presence of other organisms

Sex of some animals is determined by the temp at which they were incubated.

Increasing altitude can stunt the phenotype of some plants Increasing altitude can stunt the phenotype of some plants. This is termed ‘cline’

Presence of other individuals of the same species may control the determination of sex eg in the wrasse family Some organisms change their morphology or body shape in the presence of other potentially harmful organisms female male daphnia

Hydrangea changes colour of flower depending on soil acidity. Siamese and colour pointing. Temperature sensitive enzyme that produces melanin