CONTROL AND COORDINATION — Class 10 CBSE
Notes
1. Introduction
Living organisms respond to stimuli (like light, sound, touch, smell,
etc.).
The process by which organisms coordinate and control their
actions is called Control and Coordination.
Two systems perform this in animals:
1. Nervous System
2. Endocrine System (Hormonal)
2. Control and Coordination in Animals
(a) Nervous System
The nervous system controls actions through electrical impulses.
Main parts: Brain, Spinal Cord, Nerves
(b) Neuron (Nerve Cell)
Structural and functional unit of the nervous system.
Parts:
1. Dendrites – receive messages
2. Cell body (cyton) – processes information
3. Axon – transmits impulses
4. Axon terminals – pass signals to next neuron or effector
Path of Message Transmission:
Stimulus → Receptor → Sensory neuron → Spinal cord/brain → Motor
neuron → Effector (muscle/gland)
(c) Reflex Action
Instant, involuntary response to a stimulus (for protection).
Controlled by spinal cord, not the brain.
, Example: Touching a hot object — hand withdraws quickly.
Path: Receptor → Sensory Neuron → Spinal Cord → Motor Neuron →
Muscle
Reflex Arc: The pathway followed by nerve impulses during a reflex
action.
(d) Human Brain
Protected by: Skull (bony case) and Cerebrospinal fluid (shock
absorber)
Main parts and functions:
Part Function
Thinking, learning, reasoning, memory,
Cerebrum
voluntary actions
Cerebellum Balance and posture
Medulla Controls involuntary actions (breathing,
oblongata heartbeat)
Midbrain Controls reflex of eyes and head movements
Pons Links various parts of the brain
3. Coordination Between Nervous and Muscular System
Muscles act as effectors.
When a nerve impulse reaches muscle → it contracts.
Muscle movement uses energy (ATP).
4. Chemical Coordination in Animals (Endocrine System)
Endocrine glands secrete hormones (chemical messengers) directly
into blood.
Hormones regulate growth, metabolism, reproduction, etc.
Important Human Endocrine Glands:
Gland Hormone Function
Pituitary Growth hormone Controls growth, “Master gland”
Notes
1. Introduction
Living organisms respond to stimuli (like light, sound, touch, smell,
etc.).
The process by which organisms coordinate and control their
actions is called Control and Coordination.
Two systems perform this in animals:
1. Nervous System
2. Endocrine System (Hormonal)
2. Control and Coordination in Animals
(a) Nervous System
The nervous system controls actions through electrical impulses.
Main parts: Brain, Spinal Cord, Nerves
(b) Neuron (Nerve Cell)
Structural and functional unit of the nervous system.
Parts:
1. Dendrites – receive messages
2. Cell body (cyton) – processes information
3. Axon – transmits impulses
4. Axon terminals – pass signals to next neuron or effector
Path of Message Transmission:
Stimulus → Receptor → Sensory neuron → Spinal cord/brain → Motor
neuron → Effector (muscle/gland)
(c) Reflex Action
Instant, involuntary response to a stimulus (for protection).
Controlled by spinal cord, not the brain.
, Example: Touching a hot object — hand withdraws quickly.
Path: Receptor → Sensory Neuron → Spinal Cord → Motor Neuron →
Muscle
Reflex Arc: The pathway followed by nerve impulses during a reflex
action.
(d) Human Brain
Protected by: Skull (bony case) and Cerebrospinal fluid (shock
absorber)
Main parts and functions:
Part Function
Thinking, learning, reasoning, memory,
Cerebrum
voluntary actions
Cerebellum Balance and posture
Medulla Controls involuntary actions (breathing,
oblongata heartbeat)
Midbrain Controls reflex of eyes and head movements
Pons Links various parts of the brain
3. Coordination Between Nervous and Muscular System
Muscles act as effectors.
When a nerve impulse reaches muscle → it contracts.
Muscle movement uses energy (ATP).
4. Chemical Coordination in Animals (Endocrine System)
Endocrine glands secrete hormones (chemical messengers) directly
into blood.
Hormones regulate growth, metabolism, reproduction, etc.
Important Human Endocrine Glands:
Gland Hormone Function
Pituitary Growth hormone Controls growth, “Master gland”
