This lesson contains 42 slides, with interactive quizzes and text slides.
Items in this lesson
5.9 Neurons
Slide 1 - Slide
The Nervous system
The nervous system controls your muscles
-walk / write / exercise
-swallowing / blinking / breathing
-Central nervous system vs.
-Peripheral nervous system
Slide 2 - Slide
Which parts belong to the central nervous system?
Slide 3 - Open question
The central nervous system (CNS)
Slide 4 - Slide
Nerve cells / neurons
Sense organs (receptors) send messages: electric impulses--> to the CNS via Sensory neurons
CNS send electric impulses --> to muscles and glands (effectors) telling them wat to do via Motor neurons
Interneuronsare the connections between sensory and motorneurons.(in the spinal cord and the brain)
Slide 5 - Slide
Slide 6 - Slide
Electric impuls
Slide 7 - Slide
Slide 8 - Slide
The message is:
- is super fast
- called impulses (electrical signals)
- goes via the axon of the nerve cell
- has fatty sheat:myelin sheath around axons make the impuls travel faster
Slide 9 - Slide
Slide 10 - Slide
Responding to a stimulus
1. Receptor
Sensory cells in sense organ
2. Sensory neuron
Gathers and sends impulses from the senses
3. Inter neuron
Communicates between the different parts of the CNS
4. Spinal cord / brain
5. Motor neuron
->
Sends impulses to effector cells
6. Effector
Muscles, glands
Slide 11 - Slide
Slide 12 - Slide
You get an itch in your elbow. What is the stimulus in this reaction?
A
Receptors in your skin
B
The itch itself
C
muscles that move your arm to scratch
D
The brain that decides to scratch the elbow
Slide 13 - Quiz
You get an itch in your elbow. What is the response in this reaction?
A
Receptors in your skin
B
The itch itself
C
muscles that move your arm to scratch
D
The brain that decides to scratch the elbow
Slide 14 - Quiz
Which will send an impulse along sensory neurons?
A
Receptors in your skin
B
The spinal cord
C
The muscles in your arm
D
The brain
Slide 15 - Quiz
Which will receive an impulse by motor neurons?
A
Receptors in your skin
B
The spinal cord
C
The muscles in your arm
D
The brain
Slide 16 - Quiz
Sensory neurons carry information
A
away from the brain.
B
both to and from the brain.
C
towards the brain.
D
within the brain
Slide 17 - Quiz
True
False
Motor (efferent) neurons carry messages to the central nervous system.
The nucleus of a neuron is found outside the cell body (soma)
Slide 18 - Drag question
Motor Neuron
Inter neuron
Sensory neuron
Found in visual system, brain, and spinal cord, pass informatiion on
carry electrical impulses away from the brain and spinal cord
Take information from sense organs to the brain and spinal cord
Slide 19 - Drag question
Normal situation
In a soccer match a player kicks the ball to the goal.
The goal keeper sees the ball and he jumps and catches it.
Describe the pathway in the goal keeper's nervous system.
Slide 20 - Slide
Describe the pathway in the goal keeper's nervous system.
Slide 21 - Open question
First:
Light from the ball –>
sensory receptors of the eye –>
impulses by sensory neurones –>
impulses by interneurons in spinal cord + brain stem –>
brain (vision area).
Slide 22 - Slide
Now the keeper is aware of the ball
Now the keeper is aware of the ball 😜
Slide 23 - Slide
After that:
Brain (motor area) creates impulses ->
impulses by interneurons in brain stem + spinal cord –> impulses by motor neurons –>
muscles in legs and arms
Slide 24 - Slide
Now the keeper jumps and catches the ball!
Slide 25 - Slide
Dendrite
Cell body
Nucleus
Axon
Fatty sheath
Synapse
Slide 26 - Drag question
Nerves and neurons
Slide 27 - Slide
Slide 28 - Slide
Slide 29 - Slide
spinal cord - grey and white matter
Slide 30 - Slide
When you touch an hot object... you take away your hand very fast It goes automatically, why?
Slide 31 - Open question
Reflex arcs
When you touch an hot object... you take away your hand very fast It goes automatically, why?
Reflexes protect you
Why do you think a reflex is unconscious?
Slide 32 - Slide
Why do you think a reflex is unconscious?
Slide 33 - Open question
Reflex arcs
Why do you think a reflex is unconscious?
Impulses do not go to the brain immediately
They go to the spinal cord and back (short circuit)
Slide 34 - Slide
Reflex arcs
W
1. Stimulus=
2. Receptor=
3. Effector=
4. Response=
Slide 35 - Slide
1. stimulus is: ..... 2. receptor is: ..... 3. effector is: ..... 4. effector is: .....
Slide 36 - Open question
Reflex arcs
1. Stimulus = hot flame 2. Receptor = heat sensor in the skin
3. Effector = muscles in your arm
4. Response = moving your hand away from the hot object.
Slide 37 - Slide
How do reflexes work?
Reflexes are involuntary.
Don’t ‘think’ about them: it just happens
So fast they don’t go to the brain!
Controlled by the spinal cord.
Slide 38 - Slide
Refelex arc
warmth from the flame –> sensory receptors of the skin –> impulses by sensory neurones –> impulses by interneurons in spinal cord –> impulses by motor neurons -> muscles in the arm contract