MP4 Nervous system introduction and reflex arc

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 3,4

Unit: Homeostasis

Topic: Nervous system and neurones

Lesson outline: 3 interactive video's about 5-8min each incl MCquestions.

Remainder of the time: HW (see last slide)

Aims:

- Outline the CNS, PNS

- describe three types of neurones

- compare hormonal and neural regulation (link to the unit of homeostasis)

- describe a reflex arc pathway and outline the significance from an evolutionary perspective

Electric impuls

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

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

You get an itch in your elbow. What is the stimulus in this reaction?

1. Receptors in your skin
2. The itch itself
3. muscles that move your arm to scratch
4. The brain that decides to scratch the elbow

You get an itch in your elbow. What is the response in this reaction?

1. Receptors in your skin
2. The itch itself
3. muscles that move your arm to scratch
4. The brain that decides to scratch the elbow

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

00:19

Which two organ systems coordinate these responses and behaviors (homeostasis)?

1. circulatory system
2. muscular system
3. endocrine system
4. nervous system

01:02

How is the nerve cell adapted to it's function?

1. long body
2. thin body
3. branched ends (synapses)
4. all of the above

02:02

Components of the CNS (central nervous system)

1. skull
2. peripheral nerves
3. brain
4. spinal cord

02:11

Examples of sensory information are

1. body temperature
2. body posture
3. all answers are correct
4. light/sound

02:47

Sensory nerves receive stimuli through sensors

1. true
2. false

02:49

Motor neurones send electrical impulses to effectors

1. true
2. false

03:07

Which characteristic of living organisms does this refer to using the MRS GREN mnemonic?

01:06

What is the function of a motor neurone?

1. all answers are correct
2. pass information to effectors
3. pass information to glands
4. pass information to muscles

02:09

What is the name of the nerve endings (close to these gaps)?

1. sonopsis
2. synaps
3. synapsis
4. neurotransmitter

02:26

What type of nerve cell is seen on the left in this example? How do you know this?

1. sensory neurone, it has long dendrites and axon
2. motor neurone, it has one long axon and short dendrites

02:49

What is the name of the neurone in the middle?

1. relay neurone
2. intermediate neurone
3. all are correct
4. inter neurone

02:51

In which part of the nervous system are relay neurones found?

1. CNS Central Nervous System
2. PNS Peripheral nervous system

00:45

Note taking 5-7min

Review your knowledge on the nerves and nervous sytem. In your notebook ,create a mindmap, complete your glossary or draw an annotated diagram using the following key terms:

3 types of neurones, CNS, PNS, receptors, sensors, effectors (muscles, glands)

01:08

Aims:

You need to understand what a reflex pathway is, how it works and be able to apply this knowledge when touching a hot item. The other examples are extension material only.

01:32

Reflex arc= unconscious response to a stimulus (stimulus does initially not reach the brain)

Innate behaviour = behaviour controlled by genes. Reflex arc is an example of innate behaviour and is thus the same for organisms of the same species (regardless their environment or learning).

01:48

Last question: select the correct reflex arc pathway

1. motor -> relay -> sensory
2. sensory -> relay -> motor
3. sensory -> relay -> brain -> motor
4. sensory -> motor

www.kscience.co.uk

Review the aims of this lesson and write down any questions you have on the next slide:

Aims:

- Outline the CNS, PNS

- describe three types of neurones

- compare hormonal and neural regulation (link to the unit of homeostasis)

- describe a reflex arc pathway and outline the significance from an evolutionary perspective

What I do not understand / questions I have about the content are:

What did you think of this lessonup?

1. useful
2. somewhat useful
3. very useful
4. did not learn anything

Homework for next lesson

RSQ BFY pg 108-115

Choose 4 questions from the following:

Q2a&3 pg 217, Q1,2,4,5 pg 127 or Q16 pg 177

Complete the CNS and reflex arc WS in the handout

The end of the lesson