Tropisms and Auxins Flashcards
What are the 3 ways plants respond to stimuli
-They respond to light and grow towards it to maximise photosynthesis.
-They respond to gravity, roots grow downwards and fix plant into soil for more water and minerals
-Some plants respond to touch so they can grow around it.
Plants respond to their environment _____ than animals
Plants respond to their environment slower than animals
What is the name of the hormone in plants that stimulates growth
Auxin
Where does Auxin control growth?
The shoot and root
Where is auxin produced and how does it move to the rest of the shoot/root
-It is produced at the tip
-It dissolves in the solution of the cells and diffuses backwards along shoot/root.
What does auxin do at the shoot?
Stimulates growth causing shoot to grow
What does auxin do at the root?
Inhibits growth
What is phototropism
The plant’s response to light
What is geotropism
The plant’s response to gravity
Where do Auxins always accumulate?
Auxins always accumulate on the shaded side and the lower side of the shoot/root.
What does it mean that shoots are positively phototropic and negatively geotropic?
-It grows towards light and grows away from the ground (against gravity)
What way will a shoot grow if the sun is on the left side.
-It will grow towards the left as the auxins accumulate on the shaded side causing that side to grow faster so it bends towards light.
What does it mean that roots are negatively phototropic and positively geotropic?
It means that they grow away from light and grow towards the ground.
