BIO101 – Topic 29: Coordination and Response in Living
Organisms
Course Code: BIO 101
Course Name: General Biology
© Lesuyai Organic Guides 2025
(Original | Educational | Professional | Plagiarism-Free | A4 Format)
29.1 Introduction
Coordination and response are essential processes that enable living organisms to detect
and respond to changes in their internal and external environments. This ensures survival,
adaptation, and proper functioning of the body.
29.2 Definition of Coordination and Response
Coordination refers to the orderly working of different organs and systems of the body to
perform life processes efficiently. Response is the reaction of an organism to a stimulus.
29.3 Importance of Coordination and Response
• Helps organisms maintain homeostasis
• Enables adaptation to changing environments
• Allows organisms to detect danger and react accordingly
• Facilitates communication between body systems
29.4 Coordination in Plants
Plants respond to stimuli such as light, gravity, touch, and chemicals. These responses
are called tropic and nastic movements.
Types of Plant Responses
Phototropism: Growth of a plant towards light.
Geotropism: Response to gravity (roots grow downwards).
Thigmotropism: Response to touch, as seen in climbing plants.
Nastic Movements: Non-directional responses such as the closing of leaves in Mimosa
pudica.
29.5 Coordination in Animals
Animals use the nervous and endocrine systems to detect stimuli and coordinate body
responses. The nervous system provides fast, short-term responses, while the endocrine
system regulates long-term functions like growth and reproduction.
Organisms
Course Code: BIO 101
Course Name: General Biology
© Lesuyai Organic Guides 2025
(Original | Educational | Professional | Plagiarism-Free | A4 Format)
29.1 Introduction
Coordination and response are essential processes that enable living organisms to detect
and respond to changes in their internal and external environments. This ensures survival,
adaptation, and proper functioning of the body.
29.2 Definition of Coordination and Response
Coordination refers to the orderly working of different organs and systems of the body to
perform life processes efficiently. Response is the reaction of an organism to a stimulus.
29.3 Importance of Coordination and Response
• Helps organisms maintain homeostasis
• Enables adaptation to changing environments
• Allows organisms to detect danger and react accordingly
• Facilitates communication between body systems
29.4 Coordination in Plants
Plants respond to stimuli such as light, gravity, touch, and chemicals. These responses
are called tropic and nastic movements.
Types of Plant Responses
Phototropism: Growth of a plant towards light.
Geotropism: Response to gravity (roots grow downwards).
Thigmotropism: Response to touch, as seen in climbing plants.
Nastic Movements: Non-directional responses such as the closing of leaves in Mimosa
pudica.
29.5 Coordination in Animals
Animals use the nervous and endocrine systems to detect stimuli and coordinate body
responses. The nervous system provides fast, short-term responses, while the endocrine
system regulates long-term functions like growth and reproduction.
