1. Gene Environment Interactions

2. 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

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

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

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

6. 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

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