AQA A LEVEL BIOLOGY TROPISMS
REVISION PAPERS 2023 WITH CORRECT
QUESTIONS AND ANSWERS
What is a tropism? (Correct Answers) A growth movement in response to a stimulus
What is IAA? (Correct Answers) Indoleacetic Acid, a type of auxin
Where is IAA produced? (Correct Answers) Produced in the tips of roots & shoots
How does IAA move through a plant? (Correct Answers) Diffusion
What effect does IAA have on root cells? (Correct Answers) Inhibits cell elongation
What effect does IAA have on shoot cells? (Correct Answers) Stimulates cell elongation
Does IAA diffuse towards or away from gravity. (Correct Answers) IAA moves
downwards, Cells in the upper surface of the root will elongate more
Does IAA diffuse towards or away from water? (Correct Answers) IAA moves towards
moisture; Cells in contact with dry conditions will be stimulated to grow and elongate
Does IAA diffuse towards or away from light? (Correct Answers) IAA moves away from
light: cells near to light will grow more and elongate towards the lights;
Phototropism is a response to (Correct Answers) light
Geotropism is a response to (Correct Answers) gravity
Hydrotropism is a response to (Correct Answers) water
Shoots are (Correct Answers) positively phototropic
Roots are (Correct Answers) positively geotropic
Negative geotropism is seen in (Correct Answers) shoots
Negative phototropism is seen in (Correct Answers) roots
REVISION PAPERS 2023 WITH CORRECT
QUESTIONS AND ANSWERS
What is a tropism? (Correct Answers) A growth movement in response to a stimulus
What is IAA? (Correct Answers) Indoleacetic Acid, a type of auxin
Where is IAA produced? (Correct Answers) Produced in the tips of roots & shoots
How does IAA move through a plant? (Correct Answers) Diffusion
What effect does IAA have on root cells? (Correct Answers) Inhibits cell elongation
What effect does IAA have on shoot cells? (Correct Answers) Stimulates cell elongation
Does IAA diffuse towards or away from gravity. (Correct Answers) IAA moves
downwards, Cells in the upper surface of the root will elongate more
Does IAA diffuse towards or away from water? (Correct Answers) IAA moves towards
moisture; Cells in contact with dry conditions will be stimulated to grow and elongate
Does IAA diffuse towards or away from light? (Correct Answers) IAA moves away from
light: cells near to light will grow more and elongate towards the lights;
Phototropism is a response to (Correct Answers) light
Geotropism is a response to (Correct Answers) gravity
Hydrotropism is a response to (Correct Answers) water
Shoots are (Correct Answers) positively phototropic
Roots are (Correct Answers) positively geotropic
Negative geotropism is seen in (Correct Answers) shoots
Negative phototropism is seen in (Correct Answers) roots
