Download Nervous System III – Reflexes and Peripheral Nervous System (PNS)

Name:
Date:
Sec 3 Sci&Tec
Ms. Sulik
Nervous System III – Reflexes and Peripheral Nervous System (PNS)
Knee-jerk test
Before-During-After
Before
During
After
1) Hit the tendon with the hammer
a. Receive a message
 This is the
_
2) Signal is sent
a. Message is
3) Leg kicks out
a.
 Knee-jerk
_
occurs
1
Name:
Date:
Sec 3 Sci&Tec
Ms. Sulik
Reflexes
Reflex: a
_ and
_
Stimulus: Anything that can be
reaction to a stimulus
_ by a living organism and can
Reflex arc: The pathway taken by a
_ during a reflex.
 Basically a series of neurons
What’s happening in our bodies?
General process
1) We receive a stimulus
Knee-jerk example
The stimulus is:
_
2) A nerve impulse message is
transferred
Message is transferred along
neurons
3) This message is received and
decoded
Message is received and decoded by the
4) A new message is sent in return
5) There is a reaction
_
Message is transferred along
neurons
The reaction is:
_
CNS and PNS
Central Nervous System (CNS) is composed of
Spinal cord:
_ and
_.
_ in the nervous system that
_ from the
various parts of the body to the brain. It is like a large communication cable.
 The spinal cord is also known as the
_ centre
Peripheral Nervous System (PNS)
_ different parts of the body to the
.
Sensory receptors: The structures that pick up
into
_
and transform them
.
 Transfer impulse to
nerves
2
Name:
Date:
Sec 3 Sci&Tec
Ms. Sulik
Types of neurons
Sensory neurons
-
Transmit information from the
to the
Motor neurons
-
Transmit impulses from
to
in order to
produce movement
 Movement can be voluntary or involuntary
Interneurons
-
Neurons that
between other neurons
 Neither sensory nor motor
Reflex Pathway
1) The
impulses.
pick up a stimulus and change it into electrical
2) The
or afferent nerve carries the message to the CNS.
3) The
(found in the grey matter of the spinal cord)
received the information and interprets it. It then sends out a response signal.
4) The
muscles and makes it react.
 This reaction can be
or efferent nerve transmits the signal to the
or
3
Name:
Date:
Sec 3 Sci&Tec
Ms. Sulik
Response Time Test
General process
1) We receive a stimulus
Ruler Drop Test
The stimulus is:
_
2) A nerve impulse message is
transferred
Message is transferred along
neurons
3) This message is received and
decoded
Message is received and decoded by the
4) A new message is sent in return
5) There is a reaction
_
Message is transferred along
neurons
The reaction is:
_
Difference between knee-jerk and ruler drop test:
Knee-jerk –
reflex
Ruler test –
movement
4