Phototropism (Grade 12 NSC Matric Life Sciences): Flashcards

Plant growth response to light from specific direction

Plant hormones at growing tips controlling growth responses

Distributed evenly, equal growth on all sides of stem

More accumulate on shaded side of stem

Shaded side has more auxins, grows faster, causes bending

Growth towards light, shown by stems

Growth away from light, shown by roots

Leaves positioned to receive maximum sunlight

Covered tip: straight growth; uncovered: bends to light

The growing tip