Chapter: 3 Movement in & out of Cells

Coordination in plants

• Like animals, plants are able to respond to their environment, although usually with much slower responses than those of animals.
• In general, plants respond to stimuli by changing their rate or direction of growth.
• They may grow either towards a stimulus is said to be a positive response, and growth away from a stimulus is a negative response.
• These growth responses are called tropisms.
• Two important stimuli for plants are light and gravity.
• Growth responses to light are called phototropism.
• Growth responses to gravity are called gravitropism.
• Shoots normally grow towards light.
• They are positively phototropic.
• Roots do not usually respond to light , but in some plants , the root grows away from light.

Ziad ahmed – IGCSE-AS-A-Level-IB Biology Teacher WhatsApp: [phone]

Ziad ahmed – IGCSE-AS-A-Level-IB Biology Teacher WhatsApp: [phone]