Types of Tropisms
Biology: AQA GCSE Higher, topic 5.4.2
Tropisms
Tropisms are controlled by auxins. They are groups of responses that can be split into:
Phototropisms
- These involve growth either towards (positively phototropic) or away from (negatively phototropic) a light source.
Gravitropisms (or geotropisms)
- Growth either towards (positively gravitropic) or away from (negatively geotropic) the direction of gravity.
Test yourself on Types of Tropisms
What is a negative gravitropism?
How does the direction of growth relate to whether a tropism is positive or negative?
Why are phototropisms and gravitropisms both classed as types of tropism?
Select the correct statement in each pair