Question

8. Anita kept a potted plant near the widow Sill. To her observation, she found the stem moved in two different directions, Can you guess, why ? Give reason

Answer 1

Answer:

stem will moved toward outside of window due to the positive phototropism. and upward due to negative geotropism.

Answer 2

When a potted plant is kept near the window sill, the stem moves in two different directions. The reason is given below:

1. One direction is upwards, which is against the gravitational force. This is due to negative geotropism.

• Because of gravity, auxin, the growth hormone, is collected at the bottom of the plant.
• Thus, cell growth happens in the lower part and the stem cells at this lower part elongate.
• As a result, the shoot is seen moving in the direction opposite to gravity.
• This is how shoot shows negative geotropism.

2. Another direction is towards sunlight, which is called positive phototropism.

• Once again, the growth hormone, auxin collect in the part exposed to sunlight.
• The cells in the upper part of the stem facing light thus elongate.
• As a result, growth occurs in the direction of light.
• This is how the stem shows positive phototropism.