Class 10 Science Chapter : 6 Control and Coordination NCERT Notes 

Study Notes by Class of Achievers : Control and Coordination

Topic 1: Introduction to Control and Coordination 

– Movement in living organisms can be due to growth (e.g., plants) or responses to environmental changes (e.g., animals). 

– Control and coordination are essential for appropriate responses to stimuli.

Topic 2: Nervous System in Animals 

– Control and coordination in animals are provided by nervous and muscular tissues.

– Receptors in sense organs detect environmental changes (e.g., taste, smell).

– Nerve Impulses: 

Information travels via electrical impulses through neurons.

Impulses are transmitted across synapses using chemical signals.

2.1 Reflex Actions 

– Reflex Action: An involuntary and immediate response to a stimulus (e.g., pulling back from a flame).

– Reflex Arc: The pathway taken by nerve impulses during a reflex action, typically involving the spinal cord.

2.2 Human Brain 

– The brain is the main coordinating center, consisting of:

Fore-brain: Responsible for thinking and processing sensory information.

Mid-brain: Involuntary actions like breathing and heart rate.

Hind-brain: Coordinates balance and voluntary movements.

Topic 3: Coordination in Plants 

– Plants lack a nervous system but respond to stimuli through growth and movement.

– Types of Plant Movement:

Immediate Response: Quick movements (e.g., sensitive plants folding leaves).

Growth-Dependent Movement: Directional growth in response to stimuli (e.g., phototropism).

3.1 Tropisms

• Phototropism: Growth towards light (shoots) or away from it (roots).
• Geotropism: Growth in response to gravity (roots grow downwards).

Topic 4: Hormones in Animals

• Hormones: Chemical messengers that regulate various functions in the body.
• Adrenaline: Increases heart rate and prepares the body for fight or flight.
• Insulin: Regulates blood sugar levels.
• Thyroxin: Regulates metabolism and growth.

Quick Revision Points

• Nervous System: Fast, electrical impulses for immediate responses.
• Hormonal System: Slower, chemical signals for longer-term regulation.
• Reflex Actions: Quick, involuntary responses bypassing the brain.
• Tropisms: Directional growth in plants responding to environmental stimuli.

Remember These! 

– Mnemonic for Brain Functions:  Fore-brain (thinking), Mid-brain (involuntary actions), Hind-brain (balance).

Hormones and Functions:

– Growth hormone – stimulates growth.

– Thyroxin – regulates metabolism.

– Insulin – regulates blood sugar.

Table: Comparison of Nervous and Hormonal Control