Check sibling questions

Tropic movements

Plant movements that take place along a particular direction are called Tropic movements.

These movements can be towards the direction of the stimulus or away.

The stimulus can be gravity, light, chemicals etc. 

POSITIVE TOWARDS STIMULUS and NEGATIVE TOWARDS STIMULUS - Teachoo.jpg

Consider this example again;

RESPONSE TO STIMULI RELATED TO GROWTH - Teachoo.jpg

Here, the roots grow in the direction of gravity (downwards), this is Positive Geotropism

  • Positive; since the movement is towards stimulus 
  • Geotropism; movement due to gravity

On the other hand, shoot grows upwards opposite to the direction of gravity, this is Negative Geotropism

  • Negative; since the movement is away from stimulus
  • Geotropism; movement due to gravity

PLANT SHOWINGGEOTROPISM - Teachoo.jpg

Example of Phototropism:

Sunflowers grow towards the sunlight

RESPONSE OF THE PLANT TO THE DIRECTION OF LIGHT - Teachoo.jpg

Example of Chemotropism:

Growth of pollen tubes towards ovules in the process of reproduction in plants

CHEMOTROPISM - Teachoo.jpg

Example of Thigmotropism:

Plant tendrils clinging on to a support and growing

MOVEMENT DUE TO GROWTH IN PLANTS - Teachoo.jpg

Example of Hydrotropism:

Plants grow towards regions of having water if there is a source of water nearby

HYDROTROPISM - Teachoo.jpg

Example of Thermotropism:

The plant responds to changing temperature and the growth is impacted.

The leaves of Rhododendron start folding in cold temperatures.

THERMOTROPISM - Teachoo.jpg

 

Are ads bothering you?


Transcript

POSITIVE TOWARDS STIMULUS NEGATIVE TOWARDS STIMULUS Tropism Phototropism Geotropism Thigmotropism Hydrotropism Chemotropism Thermotropism Light Gravity Touch Water Chemicals Heat PLANT SHOWING GEOTROPISM RESPONSE OF THE PLANT TO THE DIRECTION OF LIGHT CHEMOTROPISM Pollen grain Pollen tube Ovule Carpel HYDROTROPISM THERMOTROPISM Hot Temperature Cold Temperature

Maninder Singh's photo - Co-founder, Teachoo

Made by

Maninder Singh

CA Maninder Singh is a Chartered Accountant for the past 12 years and a teacher from the past 16 years. He teaches Science, Economics, Accounting and English at Teachoo