Question

Write one example each of the following tropic movements :
(i) Positive phototropism (ii) Negative phototropism
(iii) Positive geotropism (iv) Negative geotropism
(v) Hydrotropism (vi) Chemotropism

Answer 1

positive phototropism:-The flower-stalks of this plant initially show positive phototropism until they have produced flowers.

Negative phototropism:-after fertilization the stalks curl up and eventually bury the developing pods under the soil, thus showing negative phototropism

Positive geotropism:-Primary roots and certain other portions of the root system tend to grow directly toward the centre of gravity 

Negative geotropism:-Stem mostly grows away from the centre of gravity and is thus negatively geotropic. 

hydrotropism:-The roots show positive hydrotropic response, i.e., they bend towards the water

chemotropism:-movement of Pollen tube towards ovary due to absorption of calcium and borate from style of carpel

Answer 2

examples:
positive phototropism:sunflower
negative phototropism:plant roots
negative geotropism:pneumatophores
positive geotropism:roots towards ground under gravity

hydrotropism:organism tends to grow towards hydrostatic places chemotropism:in gynoecium of plant