NCERT Notes, Chapter 7: Control & Coordination, Class 10 (Science) PDF Download

 Page 1


CHAPTER – 7
Control and Coordination
Living organisms respond and react to various stimuli like heat, light, cold, touch, 
pressure etc. Plants and animals both respond to stimuli but in different manner.
Example : withdrawl of hand on touching a hot object.
Control and Coordination in Animals
It is brought about in all animals with the help of two main systems
a) Nervous System b) Endocrine System
Nervous System :
Functions
i) To receive the information from environment
ii) To receive the information from various
body parts. (Stimuli ® Response)
iii) To act accordingly through muscles and glands.
Stimulus :  Any change in environment or within that bring about the reaction eg: 
touching a hot plate.
Response :  The reaction of our body to these changes. eg. withdrawal of our hand
How do we detect that we are touching a hot object?
Receptors : Are specialised tips of some nerve cells that detect the information 
from the environment.
Receptors
are
Sense Organs
Inner
Ear
Photo receptors
Eyes
Skin Olfactory
Receptor
(Nose)
Gustatory
Receptor
(Tongue)
Hearing/
Balance of 
the body
Visual
Stimulus
Pain
Touch
Heat
Smell
Detection
Taste
Detection
X-Science
63
Page 2


CHAPTER – 7
Control and Coordination
Living organisms respond and react to various stimuli like heat, light, cold, touch, 
pressure etc. Plants and animals both respond to stimuli but in different manner.
Example : withdrawl of hand on touching a hot object.
Control and Coordination in Animals
It is brought about in all animals with the help of two main systems
a) Nervous System b) Endocrine System
Nervous System :
Functions
i) To receive the information from environment
ii) To receive the information from various
body parts. (Stimuli ® Response)
iii) To act accordingly through muscles and glands.
Stimulus :  Any change in environment or within that bring about the reaction eg: 
touching a hot plate.
Response :  The reaction of our body to these changes. eg. withdrawal of our hand
How do we detect that we are touching a hot object?
Receptors : Are specialised tips of some nerve cells that detect the information 
from the environment.
Receptors
are
Sense Organs
Inner
Ear
Photo receptors
Eyes
Skin Olfactory
Receptor
(Nose)
Gustatory
Receptor
(Tongue)
Hearing/
Balance of 
the body
Visual
Stimulus
Pain
Touch
Heat
Smell
Detection
Taste
Detection
X-Science
63
Neuron : Structural and functional unit of nervous system.
I II III
Neuron (3 main parts)
Dendrite Cell body
and Axon
Synapse
Information is
acquired
Information
travels as an
electrical impulse
Part where
electrical signal
is converted into
chemical message
for onward transmission
to next neuron
by release of neurotransmitters
Nucleus
Dendrite
Axon
Nerve
ending
Cellpody
Structure of neuron
Fig. 7.1 (a)   P 115
Synapse : The point of contact between the terminal branches of axon of one 
neuron with the dendrite of another neuron is called synapse.
Reflex Action
A quick, sudden, immediate response of the body to the certain stimuli that 
involves Spinal cord. eg. (not brain) withdrawal of hand, knee jerk etc.
Reflex arc : The pathway through which impulses pass is called reflex arc.
X-Science
64
Page 3


CHAPTER – 7
Control and Coordination
Living organisms respond and react to various stimuli like heat, light, cold, touch, 
pressure etc. Plants and animals both respond to stimuli but in different manner.
Example : withdrawl of hand on touching a hot object.
Control and Coordination in Animals
It is brought about in all animals with the help of two main systems
a) Nervous System b) Endocrine System
Nervous System :
Functions
i) To receive the information from environment
ii) To receive the information from various
body parts. (Stimuli ® Response)
iii) To act accordingly through muscles and glands.
Stimulus :  Any change in environment or within that bring about the reaction eg: 
touching a hot plate.
Response :  The reaction of our body to these changes. eg. withdrawal of our hand
How do we detect that we are touching a hot object?
Receptors : Are specialised tips of some nerve cells that detect the information 
from the environment.
Receptors
are
Sense Organs
Inner
Ear
Photo receptors
Eyes
Skin Olfactory
Receptor
(Nose)
Gustatory
Receptor
(Tongue)
Hearing/
Balance of 
the body
Visual
Stimulus
Pain
Touch
Heat
Smell
Detection
Taste
Detection
X-Science
63
Neuron : Structural and functional unit of nervous system.
I II III
Neuron (3 main parts)
Dendrite Cell body
and Axon
Synapse
Information is
acquired
Information
travels as an
electrical impulse
Part where
electrical signal
is converted into
chemical message
for onward transmission
to next neuron
by release of neurotransmitters
Nucleus
Dendrite
Axon
Nerve
ending
Cellpody
Structure of neuron
Fig. 7.1 (a)   P 115
Synapse : The point of contact between the terminal branches of axon of one 
neuron with the dendrite of another neuron is called synapse.
Reflex Action
A quick, sudden, immediate response of the body to the certain stimuli that 
involves Spinal cord. eg. (not brain) withdrawal of hand, knee jerk etc.
Reflex arc : The pathway through which impulses pass is called reflex arc.
X-Science
64
Stimulus
­
eg. Heat
RECEPTOR
ORGAN
(SKIN)
Sensory Nerves
Spinal Cord
Motor Nerves
Response
­
eg. Withdrawal
of
Hand
EFFECTOR
ORGAN
(MUSCLE)
Refer to diagram Fig 7.2 Reflex arc
Response
Responses are of three main types
Voluntary :    Controlled by fore brain
         eg. Talking, Writing
Involuntary : Controlled by mid and hind brain
         eg. Heart beat, vomiting, regulation of heartbeat 
Reflex action : controlled by spinal cord
           eg. Withdrawl of hand on touching a hot object.
Human Nervous System
Central Nervous
System
Peripheral
Nervous
System
Autonomic
Nervous
System
(CNS (PNS) (ANS)
Brain Spinal
Cord.
Cranial
Nerves
Spinal
Nerves
Sympathetic
Nervous
System
Para
Sympathetic
Nervous
System
Arise from
the brain
Arise from
Spinal Card
Fore Brain
Mid Brain
Hind Brain
X-Science
65
Page 4


CHAPTER – 7
Control and Coordination
Living organisms respond and react to various stimuli like heat, light, cold, touch, 
pressure etc. Plants and animals both respond to stimuli but in different manner.
Example : withdrawl of hand on touching a hot object.
Control and Coordination in Animals
It is brought about in all animals with the help of two main systems
a) Nervous System b) Endocrine System
Nervous System :
Functions
i) To receive the information from environment
ii) To receive the information from various
body parts. (Stimuli ® Response)
iii) To act accordingly through muscles and glands.
Stimulus :  Any change in environment or within that bring about the reaction eg: 
touching a hot plate.
Response :  The reaction of our body to these changes. eg. withdrawal of our hand
How do we detect that we are touching a hot object?
Receptors : Are specialised tips of some nerve cells that detect the information 
from the environment.
Receptors
are
Sense Organs
Inner
Ear
Photo receptors
Eyes
Skin Olfactory
Receptor
(Nose)
Gustatory
Receptor
(Tongue)
Hearing/
Balance of 
the body
Visual
Stimulus
Pain
Touch
Heat
Smell
Detection
Taste
Detection
X-Science
63
Neuron : Structural and functional unit of nervous system.
I II III
Neuron (3 main parts)
Dendrite Cell body
and Axon
Synapse
Information is
acquired
Information
travels as an
electrical impulse
Part where
electrical signal
is converted into
chemical message
for onward transmission
to next neuron
by release of neurotransmitters
Nucleus
Dendrite
Axon
Nerve
ending
Cellpody
Structure of neuron
Fig. 7.1 (a)   P 115
Synapse : The point of contact between the terminal branches of axon of one 
neuron with the dendrite of another neuron is called synapse.
Reflex Action
A quick, sudden, immediate response of the body to the certain stimuli that 
involves Spinal cord. eg. (not brain) withdrawal of hand, knee jerk etc.
Reflex arc : The pathway through which impulses pass is called reflex arc.
X-Science
64
Stimulus
­
eg. Heat
RECEPTOR
ORGAN
(SKIN)
Sensory Nerves
Spinal Cord
Motor Nerves
Response
­
eg. Withdrawal
of
Hand
EFFECTOR
ORGAN
(MUSCLE)
Refer to diagram Fig 7.2 Reflex arc
Response
Responses are of three main types
Voluntary :    Controlled by fore brain
         eg. Talking, Writing
Involuntary : Controlled by mid and hind brain
         eg. Heart beat, vomiting, regulation of heartbeat 
Reflex action : controlled by spinal cord
           eg. Withdrawl of hand on touching a hot object.
Human Nervous System
Central Nervous
System
Peripheral
Nervous
System
Autonomic
Nervous
System
(CNS (PNS) (ANS)
Brain Spinal
Cord.
Cranial
Nerves
Spinal
Nerves
Sympathetic
Nervous
System
Para
Sympathetic
Nervous
System
Arise from
the brain
Arise from
Spinal Card
Fore Brain
Mid Brain
Hind Brain
X-Science
65
Human Brain
Human brain has three major parts or regions
a) Forebrain  b) Mid Brain  c) Hind Brain
FOREBRAIN
Most complex/specialized part of the brain is  CEREBRUM
FUNCTIONS :
1. Thinking part of the brain
2. Control the voluntary actions.
3. Store information (Memory)
4. Centre associated with HUNGER
5. Receives sensory impulses from various body parts and integrates it
Mid Brain :
HYPOTHALAMUS : Chemical co-ordination
PITUITARY GLAND : Secretes hormones
Hind Brain :
CEREBELLUM i) Controls posture and balance
ii) Control precision of voluntary actions
MEDULLA Controls involuntary actions
eg. blood pressure, salivation, vomiting
PONS Involuntary action, regulation of respiration
Fig 7.3 Human Brain
X-Science
66
Page 5


CHAPTER – 7
Control and Coordination
Living organisms respond and react to various stimuli like heat, light, cold, touch, 
pressure etc. Plants and animals both respond to stimuli but in different manner.
Example : withdrawl of hand on touching a hot object.
Control and Coordination in Animals
It is brought about in all animals with the help of two main systems
a) Nervous System b) Endocrine System
Nervous System :
Functions
i) To receive the information from environment
ii) To receive the information from various
body parts. (Stimuli ® Response)
iii) To act accordingly through muscles and glands.
Stimulus :  Any change in environment or within that bring about the reaction eg: 
touching a hot plate.
Response :  The reaction of our body to these changes. eg. withdrawal of our hand
How do we detect that we are touching a hot object?
Receptors : Are specialised tips of some nerve cells that detect the information 
from the environment.
Receptors
are
Sense Organs
Inner
Ear
Photo receptors
Eyes
Skin Olfactory
Receptor
(Nose)
Gustatory
Receptor
(Tongue)
Hearing/
Balance of 
the body
Visual
Stimulus
Pain
Touch
Heat
Smell
Detection
Taste
Detection
X-Science
63
Neuron : Structural and functional unit of nervous system.
I II III
Neuron (3 main parts)
Dendrite Cell body
and Axon
Synapse
Information is
acquired
Information
travels as an
electrical impulse
Part where
electrical signal
is converted into
chemical message
for onward transmission
to next neuron
by release of neurotransmitters
Nucleus
Dendrite
Axon
Nerve
ending
Cellpody
Structure of neuron
Fig. 7.1 (a)   P 115
Synapse : The point of contact between the terminal branches of axon of one 
neuron with the dendrite of another neuron is called synapse.
Reflex Action
A quick, sudden, immediate response of the body to the certain stimuli that 
involves Spinal cord. eg. (not brain) withdrawal of hand, knee jerk etc.
Reflex arc : The pathway through which impulses pass is called reflex arc.
X-Science
64
Stimulus
­
eg. Heat
RECEPTOR
ORGAN
(SKIN)
Sensory Nerves
Spinal Cord
Motor Nerves
Response
­
eg. Withdrawal
of
Hand
EFFECTOR
ORGAN
(MUSCLE)
Refer to diagram Fig 7.2 Reflex arc
Response
Responses are of three main types
Voluntary :    Controlled by fore brain
         eg. Talking, Writing
Involuntary : Controlled by mid and hind brain
         eg. Heart beat, vomiting, regulation of heartbeat 
Reflex action : controlled by spinal cord
           eg. Withdrawl of hand on touching a hot object.
Human Nervous System
Central Nervous
System
Peripheral
Nervous
System
Autonomic
Nervous
System
(CNS (PNS) (ANS)
Brain Spinal
Cord.
Cranial
Nerves
Spinal
Nerves
Sympathetic
Nervous
System
Para
Sympathetic
Nervous
System
Arise from
the brain
Arise from
Spinal Card
Fore Brain
Mid Brain
Hind Brain
X-Science
65
Human Brain
Human brain has three major parts or regions
a) Forebrain  b) Mid Brain  c) Hind Brain
FOREBRAIN
Most complex/specialized part of the brain is  CEREBRUM
FUNCTIONS :
1. Thinking part of the brain
2. Control the voluntary actions.
3. Store information (Memory)
4. Centre associated with HUNGER
5. Receives sensory impulses from various body parts and integrates it
Mid Brain :
HYPOTHALAMUS : Chemical co-ordination
PITUITARY GLAND : Secretes hormones
Hind Brain :
CEREBELLUM i) Controls posture and balance
ii) Control precision of voluntary actions
MEDULLA Controls involuntary actions
eg. blood pressure, salivation, vomiting
PONS Involuntary action, regulation of respiration
Fig 7.3 Human Brain
X-Science
66
PROTECTION OF BRAIN AND SPINAL CORD
Brain : Brain is protected by a fluid filled balloon which acts as shock 
absorber and enclosed in cranium (Brain Box)
Spinal Cord : Spinal Cord is enclosed in Vertebral column.
Coordination between Nervous and Muscular Tissue
Information
[collected by
Nervous tissue]
(Sensory Nerve)
Central
Nervous
System
[CNS]
Information
Processed
by
[CNS]
Decesion
made
[by CNS]
(Motor Nerves)
Message
Passed to
muscles
Muscles
[Change in shape
and arrangement
of proteins]
Contraction
[Muscle cell]
Muscle shorten
Action
Coordination in Plants
Movement dependent
on growth
Movement independent
of growth
[immediate response
to stimulus]
eg. dropping of leaves
of Touch-me-not
plant on touching it
Movement in Plants
Tropic movements
[directional movements
in response to stimulus]
Phototropism
Movement
towards light
Geotropism
Movement
towards gravity
Chemotropism
Movement
towards Chemicals/
growth of pollen
tube towards avule
Hydrotropism
Movement
towards /
water
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